31421312 has 64 divisors (see below), whose sum is σ = 70428960. Its totient is φ = 13854720.

The previous prime is 31421311. The next prime is 31421329. The reversal of 31421312 is 21312413.

It is a tau number, because it is divible by the number of its divisors (64).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31421311) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 37862 + ... + 38682.

Almost surely, 2^31421312 is an apocalyptic number.

31421312 is a gapful number since it is divisible by the number (32) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 31421312, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (35214480).

31421312 is an abundant number, since it is smaller than the sum of its proper divisors (39007648).

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

31421312 is a wasteful number, since it uses less digits than its factorization.

31421312 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 871 (or 859 counting only the distinct ones).

The product of its digits is 144, while the sum is 17.

The square root of 31421312 is about 5605.4716126299. The cubic root of 31421312 is about 315.5547861590.

Adding to 31421312 its reverse (21312413), we get a palindrome (52733725).

The spelling of 31421312 in words is "thirty-one million, four hundred twenty-one thousand, three hundred twelve".