21878296899408 has 120 divisors (see below), whose sum is σ = 61290464157000. Its totient is φ = 7285430111232.

The previous prime is 21878296899391. The next prime is 21878296899409. The reversal of 21878296899408 is 80499869287812.

21878296899408 is a `hidden beast` number, since 2 + 187 + 8 + 29 + 6 + 8 + 9 + 9 + 408 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 7420568261184 + 14457728638224 = 2724072^2 + 3802332^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21878296899409) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 627281266 + ... + 627316142.

It is an arithmetic number, because the mean of its divisors is an integer number (510753867975).

Almost surely, 2^{21878296899408} is an apocalyptic number.

It is an amenable number.

21878296899408 is an abundant number, since it is smaller than the sum of its proper divisors (39412167257592).

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

21878296899408 is a wasteful number, since it uses less digits than its factorization.

21878296899408 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 39149 (or 39140 counting only the distinct ones).

The product of its (nonzero) digits is 2006581248, while the sum is 81.

The spelling of 21878296899408 in words is "twenty-one trillion, eight hundred seventy-eight billion, two hundred ninety-six million, eight hundred ninety-nine thousand, four hundred eight".