20921626 has 12 divisors (see below), whose sum is σ = 34495146. Its totient is φ = 9509720.

The previous prime is 20921623. The next prime is 20921629. The reversal of 20921626 is 62612902.

It is an interprime number because it is at equal distance from previous prime (20921623) and next prime (20921629).

It can be written as a sum of positive squares in only one way, i.e., 20241001 + 680625 = 4499^2 + 825^2 .

It is a junction number, because it is equal to n+sod(n) for n = 20921594 and 20921603.

It is not an unprimeable number, because it can be changed into a prime (20921623) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 42985 + ... + 43468.

Almost surely, 2^20921626 is an apocalyptic number.

20921626 is a deficient number, since it is larger than the sum of its proper divisors (13573520).

20921626 is a wasteful number, since it uses less digits than its factorization.

20921626 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 86477 (or 86466 counting only the distinct ones).

The product of its (nonzero) digits is 2592, while the sum is 28.

The square root of 20921626 is about 4574.0163969973. The cubic root of 20921626 is about 275.5487708493.

The spelling of 20921626 in words is "twenty million, nine hundred twenty-one thousand, six hundred twenty-six".