21655043266101 has 16 divisors (see below), whose sum is σ = 33119925608448. Its totient is φ = 12328648772400.

The previous prime is 21655043266091. The next prime is 21655043266123. The reversal of 21655043266101 is 10166234055612.

It is not a de Polignac number, because 21655043266101 - 2¹⁰ = 21655043265077 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21655043268101) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1902563565 + ... + 1902574946.

It is an arithmetic number, because the mean of its divisors is an integer number (2069995350528).

Almost surely, 2^{21655043266101} is an apocalyptic number.

21655043266101 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

It is an amenable number.

21655043266101 is a deficient number, since it is larger than the sum of its proper divisors (11464882342347).

21655043266101 is a wasteful number, since it uses less digits than its factorization.

21655043266101 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3805138792.

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

The spelling of 21655043266101 in words is "twenty-one trillion, six hundred fifty-five billion, forty-three million, two hundred sixty-six thousand, one hundred one".