21038345388 has 72 divisors (see below), whose sum is σ = 54295719296. Its totient is φ = 6866726400.

The previous prime is 21038345381. The next prime is 21038345411. The reversal of 21038345388 is 88354383012.

21038345388 is a `hidden beast` number, since 2 + 103 + 8 + 3 + 4 + 538 + 8 = 666.

It is a super-2 number, since 2×21038345388² (a number of 21 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (21038345381) 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, 468228 + ... + 511188.

Almost surely, 2^21038345388 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21038345388, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (27147859648).

21038345388 is an abundant number, since it is smaller than the sum of its proper divisors (33257373908).

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

21038345388 is a wasteful number, since it uses less digits than its factorization.

21038345388 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 43255 (or 43250 counting only the distinct ones).

The product of its (nonzero) digits is 552960, while the sum is 45.

The spelling of 21038345388 in words is "twenty-one billion, thirty-eight million, three hundred forty-five thousand, three hundred eighty-eight".