21616319 has 6 divisors (see below), whose sum is σ = 22814280. Its totient is φ = 20478276.

The previous prime is 21616303. The next prime is 21616327. The reversal of 21616319 is 91361612.

It is not a de Polignac number, because 21616319 - 2⁴ = 21616303 is a prime.

It is a super-2 number, since 2×21616319² = 934530494219522, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21616291 and 21616300.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21616349) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 29579 + ... + 30300.

It is an arithmetic number, because the mean of its divisors is an integer number (3802380).

Almost surely, 2^21616319 is an apocalyptic number.

21616319 is a deficient number, since it is larger than the sum of its proper divisors (1197961).

21616319 is an equidigital number, since it uses as much as digits as its factorization.

21616319 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 59917 (or 59898 counting only the distinct ones).

The product of its digits is 1944, while the sum is 29.

The square root of 21616319 is about 4649.3353288400. The cubic root of 21616319 is about 278.5654476284.

The spelling of 21616319 in words is "twenty-one million, six hundred sixteen thousand, three hundred nineteen".