21978575004672 has 2112 divisors, whose sum is σ = 82251053434368. Its totient is φ = 5549064192000.

The previous prime is 21978575004641. The next prime is 21978575004697. The reversal of 21978575004672 is 27640057587912.

21978575004672 is a `hidden beast` number, since 2 + 1 + 9 + 7 + 8 + 57 + 500 + 4 + 6 + 72 = 666.

It is a tau number, because it is divible by the number of its divisors (2112).

It is an unprimeable number.

It is a polite number, since it can be written in 191 ways as a sum of consecutive naturals, for example, 65218323288 + ... + 65218323624.

Almost surely, 2^{21978575004672} is an apocalyptic number.

21978575004672 is a gapful number since it is divisible by the number (22) 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 21978575004672, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (41125526717184).

21978575004672 is an abundant number, since it is smaller than the sum of its proper divisors (60272478429696).

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

21978575004672 is a wasteful number, since it uses less digits than its factorization.

21978575004672 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 516 (or 495 counting only the distinct ones).

The product of its (nonzero) digits is 59270400, while the sum is 63.

The spelling of 21978575004672 in words is "twenty-one trillion, nine hundred seventy-eight billion, five hundred seventy-five million, four thousand, six hundred seventy-two".