21576937560 has 128 divisors (see below), whose sum is σ = 67682304000. Its totient is φ = 5492512256.

The previous prime is 21576937517. The next prime is 21576937561. The reversal of 21576937560 is 6573967512.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21576937561) 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, 1397161 + ... + 1412519.

It is an arithmetic number, because the mean of its divisors is an integer number (528768000).

Almost surely, 2^21576937560 is an apocalyptic number.

21576937560 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 21576937560, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (33841152000).

21576937560 is an abundant number, since it is smaller than the sum of its proper divisors (46105366440).

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

21576937560 is a wasteful number, since it uses less digits than its factorization.

21576937560 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15905 (or 15901 counting only the distinct ones).

The product of its (nonzero) digits is 2381400, while the sum is 51.

The spelling of 21576937560 in words is "twenty-one billion, five hundred seventy-six million, nine hundred thirty-seven thousand, five hundred sixty".