20688936 has 32 divisors (see below), whose sum is σ = 52261440. Its totient is φ = 6824448.

The previous prime is 20688931. The next prime is 20688947. The reversal of 20688936 is 63988602.

It is not an unprimeable number, because it can be changed into a prime (20688931) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2116 + ... + 6771.

It is an arithmetic number, because the mean of its divisors is an integer number (1633170).

Almost surely, 2^20688936 is an apocalyptic number.

It is an amenable number.

20688936 is an abundant number, since it is smaller than the sum of its proper divisors (31572504).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

20688936 is a wasteful number, since it uses less digits than its factorization.

20688936 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8993 (or 8989 counting only the distinct ones).

The product of its (nonzero) digits is 124416, while the sum is 42.

The square root of 20688936 is about 4548.5092063224. The cubic root of 20688936 is about 274.5234103345.

The spelling of 20688936 in words is "twenty million, six hundred eighty-eight thousand, nine hundred thirty-six".