21371384844 has 48 divisors (see below), whose sum is σ = 55509862240. Its totient is φ = 7110607680.

The previous prime is 21371384833. The next prime is 21371384857. The reversal of 21371384844 is 44848317312.

21371384844 is a `hidden beast` number, since 2 + 1 + 37 + 138 + 484 + 4 = 666.

It is a super-3 number, since 3×21371384844³ (a number of 32 digits) contains 333 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 21371384844.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 124459 + ... + 241314.

Almost surely, 2^21371384844 is an apocalyptic number.

It is an amenable number.

21371384844 is an abundant number, since it is smaller than the sum of its proper divisors (34138477396).

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

21371384844 is a wasteful number, since it uses less digits than its factorization.

21371384844 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 366327 (or 366319 counting only the distinct ones).

The product of its digits is 516096, while the sum is 45.

The spelling of 21371384844 in words is "twenty-one billion, three hundred seventy-one million, three hundred eighty-four thousand, eight hundred forty-four".