21675670727215 has 4 divisors (see below), whose sum is σ = 26010804872664. Its totient is φ = 17340536581768.

The previous prime is 21675670727209. The next prime is 21675670727233. The reversal of 21675670727215 is 51272707657612.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 21675670727215 - 2²³ = 21675662338607 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 21675670727215.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2167567072717 + ... + 2167567072726.

It is an arithmetic number, because the mean of its divisors is an integer number (6502701218166).

Almost surely, 2^{21675670727215} is an apocalyptic number.

21675670727215 is a deficient number, since it is larger than the sum of its proper divisors (4335134145449).

21675670727215 is an equidigital number, since it uses as much as digits as its factorization.

21675670727215 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4335134145448.

The product of its (nonzero) digits is 17287200, while the sum is 58.

The spelling of 21675670727215 in words is "twenty-one trillion, six hundred seventy-five billion, six hundred seventy million, seven hundred twenty-seven thousand, two hundred fifteen".