21112928380 has 24 divisors (see below), whose sum is σ = 45063990720. Its totient is φ = 8306725440.

The previous prime is 21112928363. The next prime is 21112928399. The reversal of 21112928380 is 8382921112.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 8651620 + ... + 8654059.

It is an arithmetic number, because the mean of its divisors is an integer number (1877666280).

Almost surely, 2^21112928380 is an apocalyptic number.

21112928380 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21112928380 is an abundant number, since it is smaller than the sum of its proper divisors (23951062340).

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

21112928380 is a wasteful number, since it uses less digits than its factorization.

21112928380 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17305749 (or 17305747 counting only the distinct ones).

The product of its (nonzero) digits is 13824, while the sum is 37.

The spelling of 21112928380 in words is "twenty-one billion, one hundred twelve million, nine hundred twenty-eight thousand, three hundred eighty".