20716913 has 4 divisors (see below), whose sum is σ = 23676480. Its totient is φ = 17757348.

The previous prime is 20716909. The next prime is 20716919. The reversal of 20716913 is 31961702.

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 not a de Polignac number, because 20716913 - 2² = 20716909 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (20716919) 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 3 ways as a sum of consecutive naturals, for example, 1479773 + ... + 1479786.

It is an arithmetic number, because the mean of its divisors is an integer number (5919120).

Almost surely, 2^20716913 is an apocalyptic number.

It is an amenable number.

20716913 is a deficient number, since it is larger than the sum of its proper divisors (2959567).

20716913 is an equidigital number, since it uses as much as digits as its factorization.

20716913 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2959566.

The product of its (nonzero) digits is 2268, while the sum is 29.

The square root of 20716913 is about 4551.5835705829. The cubic root of 20716913 is about 274.6470977342.

The spelling of 20716913 in words is "twenty million, seven hundred sixteen thousand, nine hundred thirteen".