21158382120 has 64 divisors (see below), whose sum is σ = 63484776000. Its totient is φ = 5641379328.

The previous prime is 21158382109. The next prime is 21158382143. The reversal of 21158382120 is 2128385112.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1405996 + ... + 1420964.

It is an arithmetic number, because the mean of its divisors is an integer number (991949625).

Almost surely, 2^21158382120 is an apocalyptic number.

21158382120 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21158382120 is an abundant number, since it is smaller than the sum of its proper divisors (42326393880).

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

21158382120 is a wasteful number, since it uses less digits than its factorization.

21158382120 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 26762 (or 26758 counting only the distinct ones).

The product of its (nonzero) digits is 7680, while the sum is 33.

The spelling of 21158382120 in words is "twenty-one billion, one hundred fifty-eight million, three hundred eighty-two thousand, one hundred twenty".