231312222 has 24 divisors (see below), whose sum is σ = 512833464. Its totient is φ = 75310704.

The previous prime is 231312209. The next prime is 231312233. The reversal of 231312222 is 222213132.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a nude number because it is divisible by every one of its digits.

It is a junction number, because it is equal to n+sod(n) for n = 231312195 and 231312204.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 148653 + ... + 150200.

It is an arithmetic number, because the mean of its divisors is an integer number (21368061).

Almost surely, 2^231312222 is an apocalyptic number.

231312222 is an abundant number, since it is smaller than the sum of its proper divisors (281521242).

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

231312222 is a wasteful number, since it uses less digits than its factorization.

231312222 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 298904 (or 298901 counting only the distinct ones).

The product of its digits is 288, while the sum is 18.

The square root of 231312222 is about 15208.9520349037. The cubic root of 231312222 is about 613.8555595402.

Adding to 231312222 its reverse (222213132), we get a palindrome (453525354).

It can be divided in two parts, 2313 and 12222, that added together give a triangular number (14535 = T₁₇₀).

The spelling of 231312222 in words is "two hundred thirty-one million, three hundred twelve thousand, two hundred twenty-two".