20688772 has 24 divisors (see below), whose sum is σ = 40047896. Its totient is φ = 9289728.

The previous prime is 20688751. The next prime is 20688817. The reversal of 20688772 is 27788602.

It can be written as a sum of positive squares in 4 ways, for example, as 8620096 + 12068676 = 2936^2 + 3474^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3453 + ... + 7300.

Almost surely, 2^20688772 is an apocalyptic number.

It is an amenable number.

20688772 is a deficient number, since it is larger than the sum of its proper divisors (19359124).

20688772 is a wasteful number, since it uses less digits than its factorization.

20688772 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10807 (or 10805 counting only the distinct ones).

The product of its (nonzero) digits is 75264, while the sum is 40.

The square root of 20688772 is about 4548.4911784019. The cubic root of 20688772 is about 274.5226849555.

The spelling of 20688772 in words is "twenty million, six hundred eighty-eight thousand, seven hundred seventy-two".