31111312 has 10 divisors (see below), whose sum is σ = 60278198. Its totient is φ = 15555648.

The previous prime is 31111307. The next prime is 31111313. The reversal of 31111312 is 21311113.

It can be written as a sum of positive squares in only one way, i.e., 25040016 + 6071296 = 5004^2 + 2464^2 .

It is a super-2 number, since 2×31111312² = 1935827468722688, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 31111292 and 31111301.

It is not an unprimeable number, because it can be changed into a prime (31111313) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 972213 + ... + 972244.

Almost surely, 2^31111312 is an apocalyptic number.

It is an amenable number.

31111312 is a deficient number, since it is larger than the sum of its proper divisors (29166886).

31111312 is a wasteful number, since it uses less digits than its factorization.

31111312 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1944465 (or 1944459 counting only the distinct ones).

The product of its digits is 18, while the sum is 13.

The square root of 31111312 is about 5577.7515183091. The cubic root of 31111312 is about 314.5136089713.

Adding to 31111312 its reverse (21311113), we get a palindrome (52422425).

The spelling of 31111312 in words is "thirty-one million, one hundred eleven thousand, three hundred twelve".