21310013 has 8 divisors (see below), whose sum is σ = 21790080. Its totient is φ = 20835360.

The previous prime is 21310007. The next prime is 21310021. The reversal of 21310013 is 31001312.

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 21310013 - 2⁴ = 21309997 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 21309976 and 21310003.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21310043) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 7193 + ... + 9713.

It is an arithmetic number, because the mean of its divisors is an integer number (2723760).

Almost surely, 2^21310013 is an apocalyptic number.

It is an amenable number.

21310013 is a deficient number, since it is larger than the sum of its proper divisors (480067).

21310013 is a wasteful number, since it uses less digits than its factorization.

21310013 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2707.

The product of its (nonzero) digits is 18, while the sum is 11.

The square root of 21310013 is about 4616.2769630948. The cubic root of 21310013 is about 277.2434140438.

Adding to 21310013 its reverse (31001312), we get a palindrome (52311325).

The spelling of 21310013 in words is "twenty-one million, three hundred ten thousand, thirteen".