31689564 has 48 divisors (see below), whose sum is σ = 80833536. Its totient is φ = 9619200.

The previous prime is 31689563. The next prime is 31689569. The reversal of 31689564 is 46598613.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31689563) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 3819 + ... + 8829.

It is an arithmetic number, because the mean of its divisors is an integer number (1684032).

Almost surely, 2^31689564 is an apocalyptic number.

31689564 is a gapful number since it is divisible by the number (34) 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 31689564, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (40416768).

31689564 is an abundant number, since it is smaller than the sum of its proper divisors (49143972).

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

31689564 is a wasteful number, since it uses less digits than its factorization.

31689564 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5066 (or 5064 counting only the distinct ones).

The product of its digits is 155520, while the sum is 42.

The square root of 31689564 is about 5629.3484525298. The cubic root of 31689564 is about 316.4502341335.

The spelling of 31689564 in words is "thirty-one million, six hundred eighty-nine thousand, five hundred sixty-four".