21597158534 has 16 divisors (see below), whose sum is σ = 37025703936. Its totient is φ = 9255424200.

The previous prime is 21597158533. The next prime is 21597158549. The reversal of 21597158534 is 43585179512.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21597158533) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 358619 + ... + 414489.

It is an arithmetic number, because the mean of its divisors is an integer number (2314106496).

Almost surely, 2^21597158534 is an apocalyptic number.

21597158534 is a deficient number, since it is larger than the sum of its proper divisors (15428545402).

21597158534 is a wasteful number, since it uses less digits than its factorization.

21597158534 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 83491.

The product of its digits is 1512000, while the sum is 50.

The spelling of 21597158534 in words is "twenty-one billion, five hundred ninety-seven million, one hundred fifty-eight thousand, five hundred thirty-four".