31689360 has 160 divisors (see below), whose sum is σ = 115706880. Its totient is φ = 7944192.

The previous prime is 31689337. The next prime is 31689367. The reversal of 31689360 is 6398613.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is not an unprimeable number, because it can be changed into a prime (31689367) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 36289 + ... + 37151.

It is an arithmetic number, because the mean of its divisors is an integer number (723168).

Almost surely, 2^31689360 is an apocalyptic number.

31689360 is a gapful number since it is divisible by the number (30) 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 31689360, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (57853440).

31689360 is an abundant number, since it is smaller than the sum of its proper divisors (84017520).

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

31689360 is a wasteful number, since it uses less digits than its factorization.

31689360 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 902 (or 890 counting only the distinct ones).

The product of its (nonzero) digits is 23328, while the sum is 36.

The square root of 31689360 is about 5629.3303331746. The cubic root of 31689360 is about 316.4495550878.

It can be divided in two parts, 316 and 89360, that added together give a triangular number (89676 = T₄₂₃).

The spelling of 31689360 in words is "thirty-one million, six hundred eighty-nine thousand, three hundred sixty".