21660455460 has 96 divisors (see below), whose sum is σ = 70348078080. Its totient is φ = 4877059968.

The previous prime is 21660455419. The next prime is 21660455477. The reversal of 21660455460 is 6455406612.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 356730 + ... + 413009.

It is an arithmetic number, because the mean of its divisors is an integer number (732792480).

Almost surely, 2^21660455460 is an apocalyptic number.

21660455460 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21660455460 is an abundant number, since it is smaller than the sum of its proper divisors (48687622620).

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

21660455460 is a wasteful number, since it uses less digits than its factorization.

21660455460 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 769825 (or 769823 counting only the distinct ones).

The product of its (nonzero) digits is 172800, while the sum is 39.

The spelling of 21660455460 in words is "twenty-one billion, six hundred sixty million, four hundred fifty-five thousand, four hundred sixty".