21120021112008 has 128 divisors (see below), whose sum is σ = 65168775302400. Its totient is φ = 5554335891456.

The previous prime is 21120021111997. The next prime is 21120021112009. The reversal of 21120021112008 is 80021112002112.

It is a Harshad number since it is a multiple of its sum of digits (21).

It is not an unprimeable number, because it can be changed into a prime (21120021112009) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 12926413 + ... + 14468316.

It is an arithmetic number, because the mean of its divisors is an integer number (509131057050).

Almost surely, 2^{21120021112008} is an apocalyptic number.

21120021112008 is a gapful number since it is divisible by the number (28) formed by its first and last digit.

It is an amenable number.

21120021112008 is an abundant number, since it is smaller than the sum of its proper divisors (44048754190392).

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

21120021112008 is a wasteful number, since it uses less digits than its factorization.

21120021112008 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 27395111 (or 27395107 counting only the distinct ones).

The product of its (nonzero) digits is 128, while the sum is 21.

The spelling of 21120021112008 in words is "twenty-one trillion, one hundred twenty billion, twenty-one million, one hundred twelve thousand, eight".