20901538 has 12 divisors (see below), whose sum is σ = 36471222. Its totient is φ = 8957760.

The previous prime is 20901509. The next prime is 20901581. The reversal of 20901538 is 83510902.

It can be written as a sum of positive squares in only one way, i.e., 12299049 + 8602489 = 3507^2 + 2933^2 .

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 106543 + ... + 106738.

Almost surely, 2^20901538 is an apocalyptic number.

20901538 is a deficient number, since it is larger than the sum of its proper divisors (15569684).

20901538 is a wasteful number, since it uses less digits than its factorization.

20901538 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 213297 (or 213290 counting only the distinct ones).

The product of its (nonzero) digits is 2160, while the sum is 28.

The square root of 20901538 is about 4571.8199877073. The cubic root of 20901538 is about 275.4605527824.

The spelling of 20901538 in words is "twenty million, nine hundred one thousand, five hundred thirty-eight".