21038317 has 4 divisors (see below), whose sum is σ = 21071680. Its totient is φ = 21004956.

The previous prime is 21038293. The next prime is 21038321. The reversal of 21038317 is 71383012.

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 21038317 - 2¹¹ = 21036269 is a prime.

It is a super-2 number, since 2×21038317² = 885221564384978, 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 = 21038291 and 21038300.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21038327) 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, 15717 + ... + 17002.

It is an arithmetic number, because the mean of its divisors is an integer number (5267920).

Almost surely, 2^21038317 is an apocalyptic number.

It is an amenable number.

21038317 is a deficient number, since it is larger than the sum of its proper divisors (33363).

21038317 is an equidigital number, since it uses as much as digits as its factorization.

21038317 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 33362.

The product of its (nonzero) digits is 1008, while the sum is 25.

The square root of 21038317 is about 4586.7545170850. The cubic root of 21038317 is about 276.0601152048.

The spelling of 21038317 in words is "twenty-one million, thirty-eight thousand, three hundred seventeen".