21369444278 has 64 divisors (see below), whose sum is σ = 42791027328. Its totient is φ = 7762452480.

The previous prime is 21369444263. The next prime is 21369444359. The reversal of 21369444278 is 87244496312.

It is a congruent number.

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, 42626 + ... + 211082.

It is an arithmetic number, because the mean of its divisors is an integer number (668609802).

Almost surely, 2^21369444278 is an apocalyptic number.

21369444278 is an abundant number, since it is smaller than the sum of its proper divisors (21421583050).

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

21369444278 is a wasteful number, since it uses less digits than its factorization.

21369444278 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 168537.

The product of its digits is 2322432, while the sum is 50.

The spelling of 21369444278 in words is "twenty-one billion, three hundred sixty-nine million, four hundred forty-four thousand, two hundred seventy-eight".