20320715 has 4 divisors (see below), whose sum is σ = 24384864. Its totient is φ = 16256568.

The previous prime is 20320711. The next prime is 20320723. The reversal of 20320715 is 51702302.

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

It is a cyclic number.

It is not a de Polignac number, because 20320715 - 2² = 20320711 is a prime.

It is a super-2 number, since 2×20320715² = 825862916222450, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20320711) 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, 2032067 + ... + 2032076.

It is an arithmetic number, because the mean of its divisors is an integer number (6096216).

Almost surely, 2^20320715 is an apocalyptic number.

20320715 is a deficient number, since it is larger than the sum of its proper divisors (4064149).

20320715 is an equidigital number, since it uses as much as digits as its factorization.

20320715 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4064148.

The product of its (nonzero) digits is 420, while the sum is 20.

The square root of 20320715 is about 4507.8503746243. The cubic root of 20320715 is about 272.8849985463.

The spelling of 20320715 in words is "twenty million, three hundred twenty thousand, seven hundred fifteen".