318211220 has 24 divisors (see below), whose sum is σ = 670173000. Its totient is φ = 126916992.

The previous prime is 318211199. The next prime is 318211237. The reversal of 318211220 is 22112813.

It can be written as a sum of positive squares in 4 ways, for example, as 26894596 + 291316624 = 5186^2 + 17068^2 .

It is a Harshad number since it is a multiple of its sum of digits (20).

It is a junction number, because it is equal to n+sod(n) for n = 318211192 and 318211201.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 15815 + ... + 29774.

It is an arithmetic number, because the mean of its divisors is an integer number (27923875).

Almost surely, 2^318211220 is an apocalyptic number.

It is an amenable number.

318211220 is an abundant number, since it is smaller than the sum of its proper divisors (351961780).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

318211220 is a wasteful number, since it uses less digits than its factorization.

318211220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 45947 (or 45945 counting only the distinct ones).

The product of its (nonzero) digits is 192, while the sum is 20.

The square root of 318211220 is about 17838.4758317520. The cubic root of 318211220 is about 682.7135086766.

The spelling of 318211220 in words is "three hundred eighteen million, two hundred eleven thousand, two hundred twenty".