18957237021 has 12 divisors (see below), whose sum is σ = 27383946720. Its totient is φ = 12637571400.

The previous prime is 18957236999. The next prime is 18957237049. The reversal of 18957237021 is 12073275981.

18957237021 is a `hidden beast` number, since 1 + 8 + 9 + 572 + 3 + 70 + 2 + 1 = 666.

It is not a de Polignac number, because 18957237021 - 2⁵ = 18957236989 is a prime.

It is a Smith number, since the sum of its digits (45) coincides with the sum of the digits of its prime factors.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18957237121) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 255600 + ... + 321318.

It is an arithmetic number, because the mean of its divisors is an integer number (2281995560).

Almost surely, 2^18957237021 is an apocalyptic number.

It is an amenable number.

18957237021 is a deficient number, since it is larger than the sum of its proper divisors (8426709699).

18957237021 is a wasteful number, since it uses less digits than its factorization.

18957237021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 97776 (or 97773 counting only the distinct ones).

The product of its (nonzero) digits is 211680, while the sum is 45.

The spelling of 18957237021 in words is "eighteen billion, nine hundred fifty-seven million, two hundred thirty-seven thousand, twenty-one".