21402988560 has 480 divisors, whose sum is σ = 79095294720. Its totient is φ = 5309466624.

The previous prime is 21402988549. The next prime is 21402988609. The reversal of 21402988560 is 6588920412.

21402988560 is a `hidden beast` number, since 2 + 1 + 4 + 0 + 2 + 9 + 88 + 560 = 666.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is an unprimeable number.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 91858204 + ... + 91858436.

It is an arithmetic number, because the mean of its divisors is an integer number (164781864).

Almost surely, 2^21402988560 is an apocalyptic number.

21402988560 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 21402988560, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (39547647360).

21402988560 is an abundant number, since it is smaller than the sum of its proper divisors (57692306160).

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

21402988560 is a wasteful number, since it uses less digits than its factorization.

21402988560 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 364 (or 309 counting only the distinct ones).

The product of its (nonzero) digits is 276480, while the sum is 45.

The spelling of 21402988560 in words is "twenty-one billion, four hundred two million, nine hundred eighty-eight thousand, five hundred sixty".