21215452564122 has 32 divisors (see below), whose sum is σ = 42497435744064. Its totient is φ = 7060730265600.

The previous prime is 21215452564093. The next prime is 21215452564157. The reversal of 21215452564122 is 22146525451212.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 77028997 + ... + 77303927.

It is an arithmetic number, because the mean of its divisors is an integer number (1328044867002).

Almost surely, 2^{21215452564122} is an apocalyptic number.

21215452564122 is an abundant number, since it is smaller than the sum of its proper divisors (21281983179942).

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

21215452564122 is a wasteful number, since it uses less digits than its factorization.

21215452564122 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 295054.

The product of its digits is 384000, while the sum is 42.

The spelling of 21215452564122 in words is "twenty-one trillion, two hundred fifteen billion, four hundred fifty-two million, five hundred sixty-four thousand, one hundred twenty-two".