21176790372 has 18 divisors (see below), whose sum is σ = 53530220198. Its totient is φ = 7058930112.

The previous prime is 21176790361. The next prime is 21176790377. The reversal of 21176790372 is 27309767112.

21176790372 is a `hidden beast` number, since 21 + 176 + 7 + 90 + 372 = 666.

It can be written as a sum of positive squares in only one way, i.e., 17565261156 + 3611529216 = 132534^2 + 60096^2 .

It is a tau number, because it is divible by the number of its divisors (18).

It is not an unprimeable number, because it can be changed into a prime (21176790377) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 294122053 + ... + 294122124.

Almost surely, 2^21176790372 is an apocalyptic number.

It is an amenable number.

21176790372 is an abundant number, since it is smaller than the sum of its proper divisors (32353429826).

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

21176790372 is a wasteful number, since it uses less digits than its factorization.

21176790372 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 588244187 (or 588244182 counting only the distinct ones).

The product of its (nonzero) digits is 222264, while the sum is 45.

The spelling of 21176790372 in words is "twenty-one billion, one hundred seventy-six million, seven hundred ninety thousand, three hundred seventy-two".