21615612312160 has 48 divisors (see below), whose sum is σ = 51247332548496. Its totient is φ = 8615692804608.

The previous prime is 21615612312067. The next prime is 21615612312163. The reversal of 21615612312160 is 6121321651612.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21615612312163) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 238643019 + ... + 238733578.

It is an arithmetic number, because the mean of its divisors is an integer number (1067652761427).

Almost surely, 2^{21615612312160} is an apocalyptic number.

21615612312160 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21615612312160 is an abundant number, since it is smaller than the sum of its proper divisors (29631720236336).

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

21615612312160 is a wasteful number, since it uses less digits than its factorization.

21615612312160 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 477376895 (or 477376887 counting only the distinct ones).

The product of its (nonzero) digits is 25920, while the sum is 37.

Adding to 21615612312160 its reverse (6121321651612), we get a palindrome (27736933963772).

The spelling of 21615612312160 in words is "twenty-one trillion, six hundred fifteen billion, six hundred twelve million, three hundred twelve thousand, one hundred sixty".