21617623795 has 4 divisors (see below), whose sum is σ = 25941148560. Its totient is φ = 17294099032.

The previous prime is 21617623789. The next prime is 21617623831. The reversal of 21617623795 is 59732671612.

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 21617623795 - 2²⁷ = 21483406067 is a prime.

It is a Smith number, since the sum of its digits (49) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax 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, 2161762375 + ... + 2161762384.

It is an arithmetic number, because the mean of its divisors is an integer number (6485287140).

Almost surely, 2^21617623795 is an apocalyptic number.

21617623795 is a deficient number, since it is larger than the sum of its proper divisors (4323524765).

21617623795 is an equidigital number, since it uses as much as digits as its factorization.

21617623795 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4323524764.

The product of its digits is 952560, while the sum is 49.

The spelling of 21617623795 in words is "twenty-one billion, six hundred seventeen million, six hundred twenty-three thousand, seven hundred ninety-five".