21158117474 has 16 divisors (see below), whose sum is σ = 34590290112. Its totient is φ = 9647629968.

The previous prime is 21158117467. The next prime is 21158117479. The reversal of 21158117474 is 47471185112.

It is not an unprimeable number, because it can be changed into a prime (21158117479) 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, 4900094 + ... + 4904409.

It is an arithmetic number, because the mean of its divisors is an integer number (2161893132).

Almost surely, 2^21158117474 is an apocalyptic number.

21158117474 is a deficient number, since it is larger than the sum of its proper divisors (13432172638).

21158117474 is a wasteful number, since it uses less digits than its factorization.

21158117474 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9804601.

The product of its digits is 62720, while the sum is 41.

The spelling of 21158117474 in words is "twenty-one billion, one hundred fifty-eight million, one hundred seventeen thousand, four hundred seventy-four".