31311612 has 36 divisors (see below), whose sum is σ = 81704896. Its totient is φ = 10100160.

The previous prime is 31311593. The next prime is 31311617. The reversal of 31311612 is 21611313.

It is a tau number, because it is divible by the number of its divisors (36).

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 congruent number.

It is not an unprimeable number, because it can be changed into a prime (31311617) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 12913 + ... + 15144.

Almost surely, 2^31311612 is an apocalyptic number.

It is an amenable number.

31311612 is an abundant number, since it is smaller than the sum of its proper divisors (50393284).

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

31311612 is a wasteful number, since it uses less digits than its factorization.

31311612 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 28098 (or 28093 counting only the distinct ones).

The product of its digits is 108, while the sum is 18.

The square root of 31311612 is about 5595.6779750089. The cubic root of 31311612 is about 315.1871299296.

Adding to 31311612 its reverse (21611313), we get a palindrome (52922925).

The spelling of 31311612 in words is "thirty-one million, three hundred eleven thousand, six hundred twelve".