21399383 has 8 divisors (see below), whose sum is σ = 21703968. Its totient is φ = 21096864.

The previous prime is 21399353. The next prime is 21399401. The reversal of 21399383 is 38399312.

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

It is a cyclic number.

It is not a de Polignac number, because 21399383 - 2⁶ = 21399319 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 (21399353) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 38141 + ... + 38697.

It is an arithmetic number, because the mean of its divisors is an integer number (2712996).

Almost surely, 2^21399383 is an apocalyptic number.

21399383 is a deficient number, since it is larger than the sum of its proper divisors (304585).

21399383 is a wasteful number, since it uses less digits than its factorization.

21399383 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1033.

The product of its digits is 34992, while the sum is 38.

The square root of 21399383 is about 4625.9467139171. The cubic root of 21399383 is about 277.6304416104.

The spelling of 21399383 in words is "twenty-one million, three hundred ninety-nine thousand, three hundred eighty-three".