20709313 has 4 divisors (see below), whose sum is σ = 20836528. Its totient is φ = 20582100.

The previous prime is 20709289. The next prime is 20709319. The reversal of 20709313 is 31390702.

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 a de Polignac number, because none of the positive numbers 2^k-20709313 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20709319) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 63363 + ... + 63688.

It is an arithmetic number, because the mean of its divisors is an integer number (5209132).

Almost surely, 2^20709313 is an apocalyptic number.

It is an amenable number.

20709313 is a deficient number, since it is larger than the sum of its proper divisors (127215).

20709313 is a wasteful number, since it uses less digits than its factorization.

20709313 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 127214.

The product of its (nonzero) digits is 1134, while the sum is 25.

The square root of 20709313 is about 4550.7486197328. The cubic root of 20709313 is about 274.6135088618.

The spelling of 20709313 in words is "twenty million, seven hundred nine thousand, three hundred thirteen".