21642103555 has 16 divisors (see below), whose sum is σ = 27508135680. Its totient is φ = 16289344512.

The previous prime is 21642103531. The next prime is 21642103579. The reversal of 21642103555 is 55530124612.

It is an interprime number because it is at equal distance from previous prime (21642103531) and next prime (21642103579).

It is not a de Polignac number, because 21642103555 - 2⁵ = 21642103523 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21642103555.

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, 198286 + ... + 287404.

It is an arithmetic number, because the mean of its divisors is an integer number (1719258480).

Almost surely, 2^21642103555 is an apocalyptic number.

21642103555 is a deficient number, since it is larger than the sum of its proper divisors (5866032125).

21642103555 is a wasteful number, since it uses less digits than its factorization.

21642103555 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 91998.

The product of its (nonzero) digits is 36000, while the sum is 34.

The spelling of 21642103555 in words is "twenty-one billion, six hundred forty-two million, one hundred three thousand, five hundred fifty-five".