21120736506018 has 32 divisors (see below), whose sum is σ = 44078316327936. Its totient is φ = 6734108526288.

The previous prime is 21120736505959. The next prime is 21120736506059. The reversal of 21120736506018 is 81060563702112.

It is a happy number.

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, 31497505 + ... + 32161067.

It is an arithmetic number, because the mean of its divisors is an integer number (1377447385248).

Almost surely, 2^{21120736506018} is an apocalyptic number.

21120736506018 is an abundant number, since it is smaller than the sum of its proper divisors (22957579821918).

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

21120736506018 is a wasteful number, since it uses less digits than its factorization.

21120736506018 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 894238.

The product of its (nonzero) digits is 120960, while the sum is 42.

The spelling of 21120736506018 in words is "twenty-one trillion, one hundred twenty billion, seven hundred thirty-six million, five hundred six thousand, eighteen".