21160665654 has 16 divisors (see below), whose sum is σ = 43780687920. Its totient is φ = 6810329120.

The previous prime is 21160665637. The next prime is 21160665661. The reversal of 21160665654 is 45656606112.

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, 60806337 + ... + 60806684.

It is an arithmetic number, because the mean of its divisors is an integer number (2736292995).

Almost surely, 2^21160665654 is an apocalyptic number.

21160665654 is an abundant number, since it is smaller than the sum of its proper divisors (22620022266).

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

21160665654 is a wasteful number, since it uses less digits than its factorization.

21160665654 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 121613055.

The product of its (nonzero) digits is 259200, while the sum is 42.

The spelling of 21160665654 in words is "twenty-one billion, one hundred sixty million, six hundred sixty-five thousand, six hundred fifty-four".