21616663259 has 8 divisors (see below), whose sum is σ = 22890172608. Its totient is φ = 20343369600.

The previous prime is 21616663253. The next prime is 21616663279. The reversal of 21616663259 is 95236661612.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a de Polignac number, because none of the positive numbers 2^k-21616663259 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21616663253) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 181934 + ... + 276284.

It is an arithmetic number, because the mean of its divisors is an integer number (2861271576).

Almost surely, 2^21616663259 is an apocalyptic number.

21616663259 is a deficient number, since it is larger than the sum of its proper divisors (1273509349).

21616663259 is a wasteful number, since it uses less digits than its factorization.

21616663259 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 107845.

The product of its digits is 699840, while the sum is 47.

The spelling of 21616663259 in words is "twenty-one billion, six hundred sixteen million, six hundred sixty-three thousand, two hundred fifty-nine".