31681472 has 56 divisors (see below), whose sum is σ = 68451984. Its totient is φ = 14487552.

The previous prime is 31681457. The next prime is 31681477. The reversal of 31681472 is 27418613.

It is a Harshad number since it is a multiple of its sum of digits (32).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31681477) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 39863 + ... + 40649.

Almost surely, 2^31681472 is an apocalyptic number.

31681472 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 31681472, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (34225992).

31681472 is an abundant number, since it is smaller than the sum of its proper divisors (36770512).

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

31681472 is a wasteful number, since it uses less digits than its factorization.

31681472 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 853 (or 843 counting only the distinct ones).

The product of its digits is 8064, while the sum is 32.

The square root of 31681472 is about 5628.6296733752. The cubic root of 31681472 is about 316.4232964190.

The spelling of 31681472 in words is "thirty-one million, six hundred eighty-one thousand, four hundred seventy-two".