21380413736 has 16 divisors (see below), whose sum is σ = 43732664640. Its totient is φ = 9718369840.

The previous prime is 21380413729. The next prime is 21380413753. The reversal of 21380413736 is 63731408312.

It is a super-3 number, since 3×21380413736³ (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 21380413736.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 121479536 + ... + 121479711.

It is an arithmetic number, because the mean of its divisors is an integer number (2733291540).

Almost surely, 2^21380413736 is an apocalyptic number.

It is an amenable number.

21380413736 is an abundant number, since it is smaller than the sum of its proper divisors (22352250904).

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

21380413736 is a wasteful number, since it uses less digits than its factorization.

21380413736 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 242959264 (or 242959260 counting only the distinct ones).

The product of its (nonzero) digits is 72576, while the sum is 38.

The spelling of 21380413736 in words is "twenty-one billion, three hundred eighty million, four hundred thirteen thousand, seven hundred thirty-six".