21319583 has 4 divisors (see below), whose sum is σ = 21408288. Its totient is φ = 21230880.

The previous prime is 21319567. The next prime is 21319603. The reversal of 21319583 is 38591312.

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 21319583 - 2⁴ = 21319567 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 (21319523) 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, 43991 + ... + 44472.

It is an arithmetic number, because the mean of its divisors is an integer number (5352072).

Almost surely, 2^21319583 is an apocalyptic number.

21319583 is a deficient number, since it is larger than the sum of its proper divisors (88705).

21319583 is an equidigital number, since it uses as much as digits as its factorization.

21319583 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 88704.

The product of its digits is 6480, while the sum is 32.

The square root of 21319583 is about 4617.3133963377. The cubic root of 21319583 is about 277.2849097544.

The spelling of 21319583 in words is "twenty-one million, three hundred nineteen thousand, five hundred eighty-three".