20968313 has 4 divisors (see below), whose sum is σ = 21107328. Its totient is φ = 20829300.

The previous prime is 20968309. The next prime is 20968331. The reversal of 20968313 is 31386902.

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 20968313 - 2² = 20968309 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 20968313.

It is not an unprimeable number, because it can be changed into a prime (20968513) 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, 69281 + ... + 69582.

It is an arithmetic number, because the mean of its divisors is an integer number (5276832).

Almost surely, 2^20968313 is an apocalyptic number.

It is an amenable number.

20968313 is a deficient number, since it is larger than the sum of its proper divisors (139015).

20968313 is a wasteful number, since it uses less digits than its factorization.

20968313 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 139014.

The product of its (nonzero) digits is 7776, while the sum is 32.

The square root of 20968313 is about 4579.1170546296. The cubic root of 20968313 is about 275.7535826575.

The spelling of 20968313 in words is "twenty million, nine hundred sixty-eight thousand, three hundred thirteen".