21115451320 has 32 divisors (see below), whose sum is σ = 47539256400. Its totient is φ = 8440937728.

The previous prime is 21115451311. The next prime is 21115451339. The reversal of 21115451320 is 2315451112.

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, 98269 + ... + 227788.

Almost surely, 2^21115451320 is an apocalyptic number.

21115451320 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21115451320 is an abundant number, since it is smaller than the sum of its proper divisors (26423805080).

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

21115451320 is a wasteful number, since it uses less digits than its factorization.

21115451320 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 327687 (or 327683 counting only the distinct ones).

The product of its (nonzero) digits is 1200, while the sum is 25.

The spelling of 21115451320 in words is "twenty-one billion, one hundred fifteen million, four hundred fifty-one thousand, three hundred twenty".