31987072 has 64 divisors (see below), whose sum is σ = 70257600. Its totient is φ = 14413824.

The previous prime is 31987063. The next prime is 31987091. The reversal of 31987072 is 27078913.

It is a tau number, because it is divible by the number of its divisors (64).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 78004 + ... + 78412.

It is an arithmetic number, because the mean of its divisors is an integer number (1097775).

Almost surely, 2^31987072 is an apocalyptic number.

31987072 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 31987072, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (35128800).

31987072 is an abundant number, since it is smaller than the sum of its proper divisors (38270528).

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

31987072 is a wasteful number, since it uses less digits than its factorization.

31987072 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 483 (or 471 counting only the distinct ones).

The product of its (nonzero) digits is 21168, while the sum is 37.

The square root of 31987072 is about 5655.7114494995. The cubic root of 31987072 is about 317.4374506331.

The spelling of 31987072 in words is "thirty-one million, nine hundred eighty-seven thousand, seventy-two".