31031712 has 144 divisors (see below), whose sum is σ = 95528160. Its totient is φ = 9524736.

The previous prime is 31031687. The next prime is 31031723. The reversal of 31031712 is 21713013.

It is a tau number, because it is divible by the number of its divisors (144).

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

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 289963 + ... + 290069.

It is an arithmetic number, because the mean of its divisors is an integer number (663390).

Almost surely, 2^31031712 is an apocalyptic number.

31031712 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 31031712, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (47764080).

31031712 is an abundant number, since it is smaller than the sum of its proper divisors (64496448).

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

31031712 is a wasteful number, since it uses less digits than its factorization.

31031712 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 195 (or 184 counting only the distinct ones).

The product of its (nonzero) digits is 126, while the sum is 18.

The square root of 31031712 is about 5570.6114565638. The cubic root of 31031712 is about 314.2451464363.

Adding to 31031712 its reverse (21713013), we get a palindrome (52744725).

The spelling of 31031712 in words is "thirty-one million, thirty-one thousand, seven hundred twelve".