21177286320 has 160 divisors (see below), whose sum is σ = 68313341952. Its totient is φ = 5422683136.

The previous prime is 21177286313. The next prime is 21177286343. The reversal of 21177286320 is 2368277112.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 580129 + ... + 615551.

Almost surely, 2^21177286320 is an apocalyptic number.

21177286320 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21177286320, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (34156670976).

21177286320 is an abundant number, since it is smaller than the sum of its proper divisors (47136055632).

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

21177286320 is a wasteful number, since it uses less digits than its factorization.

21177286320 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 35539 (or 35533 counting only the distinct ones).

The product of its (nonzero) digits is 56448, while the sum is 39.

The spelling of 21177286320 in words is "twenty-one billion, one hundred seventy-seven million, two hundred eighty-six thousand, three hundred twenty".