21330756380 has 24 divisors (see below), whose sum is σ = 45297902160. Its totient is φ = 8436433280.

The previous prime is 21330756379. The next prime is 21330756389. The reversal of 21330756380 is 8365703312.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21330756389) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 5990006 + ... + 5993565.

It is an arithmetic number, because the mean of its divisors is an integer number (1887412590).

Almost surely, 2^21330756380 is an apocalyptic number.

21330756380 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21330756380 is an abundant number, since it is smaller than the sum of its proper divisors (23967145780).

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

21330756380 is a wasteful number, since it uses less digits than its factorization.

21330756380 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11983669 (or 11983667 counting only the distinct ones).

The product of its (nonzero) digits is 90720, while the sum is 38.

The spelling of 21330756380 in words is "twenty-one billion, three hundred thirty million, seven hundred fifty-six thousand, three hundred eighty".