20318789 has 4 divisors (see below), whose sum is σ = 20547180. Its totient is φ = 20090400.

The previous prime is 20318761. The next prime is 20318797. The reversal of 20318789 is 98781302.

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

It can be written as a sum of positive squares in 2 ways, for example, as 7236100 + 13082689 = 2690^2 + 3617^2 .

It is a cyclic number.

It is not a de Polignac number, because 20318789 - 2²⁰ = 19270213 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20318759) 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, 114062 + ... + 114239.

It is an arithmetic number, because the mean of its divisors is an integer number (5136795).

Almost surely, 2^20318789 is an apocalyptic number.

It is an amenable number.

20318789 is a deficient number, since it is larger than the sum of its proper divisors (228391).

20318789 is an equidigital number, since it uses as much as digits as its factorization.

20318789 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 228390.

The product of its (nonzero) digits is 24192, while the sum is 38.

The square root of 20318789 is about 4507.6367422409. The cubic root of 20318789 is about 272.8763769154.

The spelling of 20318789 in words is "twenty million, three hundred eighteen thousand, seven hundred eighty-nine".