21455031451220 has 24 divisors (see below), whose sum is σ = 45148082630784. Its totient is φ = 8564390374176.

The previous prime is 21455031451207. The next prime is 21455031451229. The reversal of 21455031451220 is 2215413055412.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21455031451229) 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, 1101377912 + ... + 1101397391.

It is an arithmetic number, because the mean of its divisors is an integer number (1881170109616).

Almost surely, 2^{21455031451220} is an apocalyptic number.

21455031451220 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21455031451220 is an abundant number, since it is smaller than the sum of its proper divisors (23693051179564).

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

21455031451220 is a wasteful number, since it uses less digits than its factorization.

21455031451220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2202775799 (or 2202775797 counting only the distinct ones).

The product of its (nonzero) digits is 48000, while the sum is 35.

The spelling of 21455031451220 in words is "twenty-one trillion, four hundred fifty-five billion, thirty-one million, four hundred fifty-one thousand, two hundred twenty".