21115664662 has 16 divisors (see below), whose sum is σ = 31743228240. Its totient is φ = 10534606848.

The previous prime is 21115664627. The next prime is 21115664681. The reversal of 21115664662 is 26646651112.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 4866558 + ... + 4870894.

It is an arithmetic number, because the mean of its divisors is an integer number (1983951765).

Almost surely, 2^21115664662 is an apocalyptic number.

21115664662 is a deficient number, since it is larger than the sum of its proper divisors (10627563578).

21115664662 is a wasteful number, since it uses less digits than its factorization.

21115664662 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9135.

The product of its digits is 103680, while the sum is 40.

The spelling of 21115664662 in words is "twenty-one billion, one hundred fifteen million, six hundred sixty-four thousand, six hundred sixty-two".