31389672 has 48 divisors (see below), whose sum is σ = 82844640. Its totient is φ = 9909792.

The previous prime is 31389671. The next prime is 31389697. The reversal of 31389672 is 27698313.

It is a self number, because there is not a number n which added to its sum of digits gives 31389672.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31389671) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 6853 + ... + 10475.

It is an arithmetic number, because the mean of its divisors is an integer number (1725930).

Almost surely, 2^31389672 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 31389672, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (41422320).

31389672 is an abundant number, since it is smaller than the sum of its proper divisors (51454968).

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

31389672 is a wasteful number, since it uses less digits than its factorization.

31389672 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3670 (or 3647 counting only the distinct ones).

The product of its digits is 54432, while the sum is 39.

The square root of 31389672 is about 5602.6486593396. The cubic root of 31389672 is about 315.4488335864.

The spelling of 31389672 in words is "thirty-one million, three hundred eighty-nine thousand, six hundred seventy-two".