21445406752 has 48 divisors (see below), whose sum is σ = 52638731712. Its totient is φ = 8355352320.

The previous prime is 21445406713. The next prime is 21445406767. The reversal of 21445406752 is 25760454412.

It is a happy number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 4349283 + ... + 4354210.

It is an arithmetic number, because the mean of its divisors is an integer number (1096640244).

Almost surely, 2^21445406752 is an apocalyptic number.

21445406752 is a gapful number since it is divisible by the number (22) formed by its first and last digit.

It is an amenable number.

21445406752 is an abundant number, since it is smaller than the sum of its proper divisors (31193324960).

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

21445406752 is a wasteful number, since it uses less digits than its factorization.

21445406752 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8703521 (or 8703513 counting only the distinct ones).

The product of its (nonzero) digits is 268800, while the sum is 40.

The spelling of 21445406752 in words is "twenty-one billion, four hundred forty-five million, four hundred six thousand, seven hundred fifty-two".