21674535165 has 12 divisors (see below), whose sum is σ = 37569194364. Its totient is φ = 11559752064.

The previous prime is 21674535121. The next prime is 21674535173. The reversal of 21674535165 is 56153547612.

21674535165 is a `hidden beast` number, since 2 + 16 + 74 + 53 + 516 + 5 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 13131784836 + 8542750329 = 114594^2 + 92427^2 .

It is not a de Polignac number, because 21674535165 - 2²⁰ = 21673486589 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (45), and also a Moran number because the ratio is a prime number: 481656337 = 21674535165 / (2 + 1 + 6 + 7 + 4 + 5 + 3 + 5 + 1 + 6 + 5).

It is a self number, because there is not a number n which added to its sum of digits gives 21674535165.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 240828124 + ... + 240828213.

It is an arithmetic number, because the mean of its divisors is an integer number (3130766197).

Almost surely, 2^21674535165 is an apocalyptic number.

It is an amenable number.

21674535165 is a deficient number, since it is larger than the sum of its proper divisors (15894659199).

21674535165 is a wasteful number, since it uses less digits than its factorization.

21674535165 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 481656348 (or 481656345 counting only the distinct ones).

The product of its digits is 756000, while the sum is 45.

The spelling of 21674535165 in words is "twenty-one billion, six hundred seventy-four million, five hundred thirty-five thousand, one hundred sixty-five".