21703013 has 4 divisors (see below), whose sum is σ = 21752448. Its totient is φ = 21653580.

The previous prime is 21703009. The next prime is 21703021. The reversal of 21703013 is 31030712.

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 21703013 - 2² = 21703009 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21702982 and 21703000.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21703093) 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, 24053 + ... + 24938.

It is an arithmetic number, because the mean of its divisors is an integer number (5438112).

Almost surely, 2^21703013 is an apocalyptic number.

It is an amenable number.

21703013 is a deficient number, since it is larger than the sum of its proper divisors (49435).

21703013 is an equidigital number, since it uses as much as digits as its factorization.

21703013 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 49434.

The product of its (nonzero) digits is 126, while the sum is 17.

The square root of 21703013 is about 4658.6492677599. The cubic root of 21703013 is about 278.9373539883.

Adding to 21703013 its reverse (31030712), we get a palindrome (52733725).

The spelling of 21703013 in words is "twenty-one million, seven hundred three thousand, thirteen".