31213230 has 32 divisors (see below), whose sum is σ = 75282048. Its totient is φ = 8282400.

The previous prime is 31213213. The next prime is 31213243. The reversal of 31213230 is 3231213.

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

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, 3865 + ... + 8795.

It is an arithmetic number, because the mean of its divisors is an integer number (2352564).

Almost surely, 2^31213230 is an apocalyptic number.

31213230 is a gapful number since it is divisible by the number (30) formed by its first and last digit.

31213230 is an abundant number, since it is smaller than the sum of its proper divisors (44068818).

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

31213230 is a wasteful number, since it uses less digits than its factorization.

31213230 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5152.

The product of its (nonzero) digits is 108, while the sum is 15.

The square root of 31213230 is about 5586.8801669626. The cubic root of 31213230 is about 314.8566745295.

Adding to 31213230 its reverse (3231213), we get a palindrome (34444443).

The spelling of 31213230 in words is "thirty-one million, two hundred thirteen thousand, two hundred thirty".