21359617 has 4 divisors (see below), whose sum is σ = 22288320. Its totient is φ = 20430916.

The previous prime is 21359603. The next prime is 21359621. The reversal of 21359617 is 71695312.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 21359617 - 2⁷ = 21359489 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21359627) 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, 464317 + ... + 464362.

It is an arithmetic number, because the mean of its divisors is an integer number (5572080).

Almost surely, 2^21359617 is an apocalyptic number.

It is an amenable number.

21359617 is a deficient number, since it is larger than the sum of its proper divisors (928703).

21359617 is an equidigital number, since it uses as much as digits as its factorization.

21359617 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 928702.

The product of its digits is 11340, while the sum is 34.

The square root of 21359617 is about 4621.6465680534. The cubic root of 21359617 is about 277.4583634742.

The spelling of 21359617 in words is "twenty-one million, three hundred fifty-nine thousand, six hundred seventeen".