21604323463 has 4 divisors (see below), whose sum is σ = 21926776120. Its totient is φ = 21281870808.

The previous prime is 21604323451. The next prime is 21604323467. The reversal of 21604323463 is 36432340612.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21604323463 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21604323467) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 161226228 + ... + 161226361.

It is an arithmetic number, because the mean of its divisors is an integer number (5481694030).

Almost surely, 2^21604323463 is an apocalyptic number.

21604323463 is a deficient number, since it is larger than the sum of its proper divisors (322452657).

21604323463 is an equidigital number, since it uses as much as digits as its factorization.

21604323463 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 322452656.

The product of its (nonzero) digits is 62208, while the sum is 34.

The spelling of 21604323463 in words is "twenty-one billion, six hundred four million, three hundred twenty-three thousand, four hundred sixty-three".