20731323 has 4 divisors (see below), whose sum is σ = 27641768. Its totient is φ = 13820880.

The previous prime is 20731309. The next prime is 20731327. The reversal of 20731323 is 32313702.

It is a semiprime because it is the product of two primes.

It is not a de Polignac number, because 20731323 - 2⁴ = 20731307 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 20731323.

It is not an unprimeable number, because it can be changed into a prime (20731327) 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, 3455218 + ... + 3455223.

It is an arithmetic number, because the mean of its divisors is an integer number (6910442).

Almost surely, 2^20731323 is an apocalyptic number.

20731323 is a deficient number, since it is larger than the sum of its proper divisors (6910445).

20731323 is an equidigital number, since it uses as much as digits as its factorization.

20731323 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6910444.

The product of its (nonzero) digits is 756, while the sum is 21.

The square root of 20731323 is about 4553.1662609661. The cubic root of 20731323 is about 274.7107614571.

The spelling of 20731323 in words is "twenty million, seven hundred thirty-one thousand, three hundred twenty-three".