20772172 has 6 divisors (see below), whose sum is σ = 36351308. Its totient is φ = 10386084.

The previous prime is 20772137. The next prime is 20772173. The reversal of 20772172 is 27127702.

It is a self number, because there is not a number n which added to its sum of digits gives 20772172.

It is not an unprimeable number, because it can be changed into a prime (20772173) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2596518 + ... + 2596525.

Almost surely, 2^20772172 is an apocalyptic number.

It is an amenable number.

20772172 is a deficient number, since it is larger than the sum of its proper divisors (15579136).

20772172 is a wasteful number, since it uses less digits than its factorization.

20772172 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5193047 (or 5193045 counting only the distinct ones).

The product of its (nonzero) digits is 2744, while the sum is 28.

The square root of 20772172 is about 4557.6498329731. The cubic root of 20772172 is about 274.8910731134.

Adding to 20772172 its reverse (27127702), we get a palindrome (47899874).

The spelling of 20772172 in words is "twenty million, seven hundred seventy-two thousand, one hundred seventy-two".