21615116360 has 128 divisors (see below), whose sum is σ = 51846480000. Its totient is φ = 8095610880.

The previous prime is 21615116339. The next prime is 21615116363. The reversal of 21615116360 is 6361151612.

It is not an unprimeable number, because it can be changed into a prime (21615116363) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 8511971 + ... + 8514509.

It is an arithmetic number, because the mean of its divisors is an integer number (405050625).

Almost surely, 2^21615116360 is an apocalyptic number.

21615116360 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 21615116360, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (25923240000).

21615116360 is an abundant number, since it is smaller than the sum of its proper divisors (30231363640).

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

21615116360 is a wasteful number, since it uses less digits than its factorization.

21615116360 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2799 (or 2795 counting only the distinct ones).

The product of its (nonzero) digits is 6480, while the sum is 32.

Adding to 21615116360 its reverse (6361151612), we get a palindrome (27976267972).

The spelling of 21615116360 in words is "twenty-one billion, six hundred fifteen million, one hundred sixteen thousand, three hundred sixty".