21134872690 has 16 divisors (see below), whose sum is σ = 38165100480. Its totient is φ = 8426764720.

The previous prime is 21134872613. The next prime is 21134872709. The reversal of 21134872690 is 9627843112.

It is a super-2 number, since 2×21134872690² (a number of 21 digits) contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3394780 + ... + 3400999.

It is an arithmetic number, because the mean of its divisors is an integer number (2385318780).

Almost surely, 2^21134872690 is an apocalyptic number.

21134872690 is a deficient number, since it is larger than the sum of its proper divisors (17030227790).

21134872690 is a wasteful number, since it uses less digits than its factorization.

21134872690 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6796097.

The product of its (nonzero) digits is 145152, while the sum is 43.

The spelling of 21134872690 in words is "twenty-one billion, one hundred thirty-four million, eight hundred seventy-two thousand, six hundred ninety".