21355457573420 has 12 divisors (see below), whose sum is σ = 44846460904224. Its totient is φ = 8542183029360.

The previous prime is 21355457573413. The next prime is 21355457573521. The reversal of 21355457573420 is 2437575455312.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 533886439316 + ... + 533886439355.

It is an arithmetic number, because the mean of its divisors is an integer number (3737205075352).

Almost surely, 2^{21355457573420} is an apocalyptic number.

21355457573420 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21355457573420 is an abundant number, since it is smaller than the sum of its proper divisors (23491003330804).

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

21355457573420 is a wasteful number, since it uses less digits than its factorization.

21355457573420 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1067772878680 (or 1067772878678 counting only the distinct ones).

The product of its (nonzero) digits is 17640000, while the sum is 53.

The spelling of 21355457573420 in words is "twenty-one trillion, three hundred fifty-five billion, four hundred fifty-seven million, five hundred seventy-three thousand, four hundred twenty".