31481688 has 128 divisors (see below), whose sum is σ = 97182720. Its totient is φ = 8294400.

The previous prime is 31481683. The next prime is 31481701. The reversal of 31481688 is 88618413.

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 (31481683) 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 31 ways as a sum of consecutive naturals, for example, 208413 + ... + 208563.

It is an arithmetic number, because the mean of its divisors is an integer number (759240).

Almost surely, 2^31481688 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 31481688, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (48591360).

31481688 is an abundant number, since it is smaller than the sum of its proper divisors (65701032).

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

31481688 is a wasteful number, since it uses less digits than its factorization.

31481688 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 257 (or 253 counting only the distinct ones).

The product of its digits is 36864, while the sum is 39.

The square root of 31481688 is about 5610.8544803800. The cubic root of 31481688 is about 315.7567695138.

The spelling of 31481688 in words is "thirty-one million, four hundred eighty-one thousand, six hundred eighty-eight".