21177702072 has 40 divisors (see below), whose sum is σ = 59317176600. Its totient is φ = 7059233808.

The previous prime is 21177702061. The next prime is 21177702083. The reversal of 21177702072 is 27020777112.

It is an interprime number because it is at equal distance from previous prime (21177702061) and next prime (21177702083).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 9 ways as a sum of consecutive naturals, for example, 16340172 + ... + 16341467.

It is an arithmetic number, because the mean of its divisors is an integer number (1482929415).

Almost surely, 2^21177702072 is an apocalyptic number.

It is an amenable number.

21177702072 is an abundant number, since it is smaller than the sum of its proper divisors (38139474528).

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

21177702072 is a wasteful number, since it uses less digits than its factorization.

21177702072 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 32681657 (or 32681644 counting only the distinct ones).

The product of its (nonzero) digits is 19208, while the sum is 36.

The spelling of 21177702072 in words is "twenty-one billion, one hundred seventy-seven million, seven hundred two thousand, seventy-two".