21975910464 has 224 divisors, whose sum is σ = 63222347520. Its totient is φ = 6715957248.

The previous prime is 21975910417. The next prime is 21975910477. The reversal of 21975910464 is 46401957912.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (48).

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 20105502 + ... + 20106594.

Almost surely, 2^21975910464 is an apocalyptic number.

21975910464 is a gapful number since it is divisible by the number (24) 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 21975910464, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (31611173760).

21975910464 is an abundant number, since it is smaller than the sum of its proper divisors (41246437056).

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

21975910464 is a wasteful number, since it uses less digits than its factorization.

21975910464 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1317 (or 1307 counting only the distinct ones).

The product of its (nonzero) digits is 544320, while the sum is 48.

The spelling of 21975910464 in words is "twenty-one billion, nine hundred seventy-five million, nine hundred ten thousand, four hundred sixty-four".