20712931 has 8 divisors (see below), whose sum is σ = 21700800. Its totient is φ = 19743360.

The previous prime is 20712917. The next prime is 20712973. The reversal of 20712931 is 13921702.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20712931 is a prime.

It is a super-2 number, since 2×20712931² = 858051021221522, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 20712896 and 20712905.

It is not an unprimeable number, because it can be changed into a prime (20712331) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2230 + ... + 6811.

It is an arithmetic number, because the mean of its divisors is an integer number (2712600).

Almost surely, 2^20712931 is an apocalyptic number.

20712931 is a deficient number, since it is larger than the sum of its proper divisors (987869).

20712931 is an equidigital number, since it uses as much as digits as its factorization.

20712931 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9149.

The product of its (nonzero) digits is 756, while the sum is 25.

The square root of 20712931 is about 4551.1461193858. The cubic root of 20712931 is about 274.6294999576.

The spelling of 20712931 in words is "twenty million, seven hundred twelve thousand, nine hundred thirty-one".