20957090 has 64 divisors (see below), whose sum is σ = 49828608. Its totient is φ = 6144000.

The previous prime is 20957089. The next prime is 20957113. The reversal of 20957090 is 9075902.

It is a Smith number, since the sum of its digits (32) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Curzon number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 12290 + ... + 13890.

It is an arithmetic number, because the mean of its divisors is an integer number (778572).

Almost surely, 2^20957090 is an apocalyptic number.

20957090 is an abundant number, since it is smaller than the sum of its proper divisors (28871518).

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

20957090 is a wasteful number, since it uses less digits than its factorization.

20957090 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1643.

The product of its (nonzero) digits is 5670, while the sum is 32.

The square root of 20957090 is about 4577.8914360216. The cubic root of 20957090 is about 275.7043761116.

The spelling of 20957090 in words is "twenty million, nine hundred fifty-seven thousand, ninety".