21118957679390 has 16 divisors (see below), whose sum is σ = 38171858780880. Its totient is φ = 8412530858880.

The previous prime is 21118957679381. The next prime is 21118957679411. The reversal of 21118957679390 is 9397675981112.

It is a self number, because there is not a number n which added to its sum of digits gives 21118957679390.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 4381524080 + ... + 4381528899.

It is an arithmetic number, because the mean of its divisors is an integer number (2385741173805).

Almost surely, 2^{21118957679390} is an apocalyptic number.

21118957679390 is a deficient number, since it is larger than the sum of its proper divisors (17052901101490).

21118957679390 is a wasteful number, since it uses less digits than its factorization.

21118957679390 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8763053227.

The product of its (nonzero) digits is 51438240, while the sum is 68.

The spelling of 21118957679390 in words is "twenty-one trillion, one hundred eighteen billion, nine hundred fifty-seven million, six hundred seventy-nine thousand, three hundred ninety".