21601316160 has 84 divisors (see below), whose sum is σ = 74299536948. Its totient is φ = 5760350208.

The previous prime is 21601316089. The next prime is 21601316161. The reversal of 21601316160 is 6161310612.

21601316160 is a `hidden beast` number, since 2 + 16 + 0 + 1 + 31 + 616 + 0 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 8698173696 + 12903142464 = 93264^2 + 113592^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21601316161) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 3747349 + ... + 3753108.

It is an arithmetic number, because the mean of its divisors is an integer number (884518297).

Almost surely, 2^21601316160 is an apocalyptic number.

21601316160 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21601316160 is an abundant number, since it is smaller than the sum of its proper divisors (52698220788).

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

21601316160 is a wasteful number, since it uses less digits than its factorization.

21601316160 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7500480 (or 7500467 counting only the distinct ones).

The product of its (nonzero) digits is 1296, while the sum is 27.

Adding to 21601316160 its reverse (6161310612), we get a palindrome (27762626772).

The spelling of 21601316160 in words is "twenty-one billion, six hundred one million, three hundred sixteen thousand, one hundred sixty".