1. If the root level is zero, a binary tree can have a maximum of 2l nodes at level l.
2. In a binary tree with one or two children, the number of leaf nodes (nodes without children) is one greater than the number of nodes with two children.
3. If the height of a binary tree is ‘h’ and the height of a leaf node is one, the tree can have a maximum of 2h-1 nodes.
4. If a binary tree contains L leaf nodes, it must have at least L+1 levels.
5. The minimum number of levels or height of a binary tree with n nodes is log2(n+1).
6. Log2n and n are the minimum and greatest heights of a binary tree with n nodes, respectively.
7. There are (n+1) null references in a binary tree with n nodes.