20913317 has 4 divisors (see below), whose sum is σ = 21267840. Its totient is φ = 20558796.

The previous prime is 20913293. The next prime is 20913329. The reversal of 20913317 is 71331902.

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 20913317 - 2¹⁸ = 20651173 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 (20913367) 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, 177173 + ... + 177290.

It is an arithmetic number, because the mean of its divisors is an integer number (5316960).

Almost surely, 2^20913317 is an apocalyptic number.

It is an amenable number.

20913317 is a deficient number, since it is larger than the sum of its proper divisors (354523).

20913317 is an equidigital number, since it uses as much as digits as its factorization.

20913317 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 354522.

The product of its (nonzero) digits is 1134, while the sum is 26.

The square root of 20913317 is about 4573.1080240904. The cubic root of 20913317 is about 275.5122880588.

The spelling of 20913317 in words is "twenty million, nine hundred thirteen thousand, three hundred seventeen".