312131220 has 48 divisors (see below), whose sum is σ = 925380288. Its totient is φ = 78338560.

The previous prime is 312131207. The next prime is 312131233. The reversal of 312131220 is 22131213.

It is an interprime number because it is at equal distance from previous prime (312131207) and next prime (312131233).

It is a Harshad number since it is a multiple of its sum of digits (15).

It is a self number, because there is not a number n which added to its sum of digits gives 312131220.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 151986 + ... + 154025.

It is an arithmetic number, because the mean of its divisors is an integer number (19278756).

Almost surely, 2^312131220 is an apocalyptic number.

312131220 is a gapful number since it is divisible by the number (30) formed by its first and last digit.

It is an amenable number.

312131220 is an abundant number, since it is smaller than the sum of its proper divisors (613249068).

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

312131220 is a wasteful number, since it uses less digits than its factorization.

312131220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 306040 (or 306038 counting only the distinct ones).

The product of its (nonzero) digits is 72, while the sum is 15.

The square root of 312131220 is about 17667.2357769969. The cubic root of 312131220 is about 678.3373596275.

Adding to 312131220 its reverse (22131213), we get a palindrome (334262433).

The spelling of 312131220 in words is "three hundred twelve million, one hundred thirty-one thousand, two hundred twenty".