21725544456 has 192 divisors, whose sum is σ = 73439308800. Its totient is φ = 5636822400.

The previous prime is 21725544437. The next prime is 21725544461. The reversal of 21725544456 is 65444552712.

21725544456 is a `hidden beast` number, since 2 + 1 + 7 + 2 + 554 + 44 + 56 = 666.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 7311051 + ... + 7314021.

It is an arithmetic number, because the mean of its divisors is an integer number (382496400).

Almost surely, 2^21725544456 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21725544456, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (36719654400).

21725544456 is an abundant number, since it is smaller than the sum of its proper divisors (51713764344).

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

21725544456 is a wasteful number, since it uses less digits than its factorization.

21725544456 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4320 (or 4313 counting only the distinct ones).

The product of its digits is 1344000, while the sum is 45.

The spelling of 21725544456 in words is "twenty-one billion, seven hundred twenty-five million, five hundred forty-four thousand, four hundred fifty-six".