31481812 has 6 divisors (see below), whose sum is σ = 55093178. Its totient is φ = 15740904.

The previous prime is 31481767. The next prime is 31481819. The reversal of 31481812 is 21818413.

It can be written as a sum of positive squares in only one way, i.e., 28772496 + 2709316 = 5364^2 + 1646^2 .

It is a super-2 number, since 2×31481812² = 1982208973606688, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31481819) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3935223 + ... + 3935230.

Almost surely, 2^31481812 is an apocalyptic number.

It is an amenable number.

31481812 is a deficient number, since it is larger than the sum of its proper divisors (23611366).

31481812 is a wasteful number, since it uses less digits than its factorization.

31481812 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7870457 (or 7870455 counting only the distinct ones).

The product of its digits is 1536, while the sum is 28.

The square root of 31481812 is about 5610.8655303794. The cubic root of 31481812 is about 315.7571840806.

The spelling of 31481812 in words is "thirty-one million, four hundred eighty-one thousand, eight hundred twelve".