31443664 has 40 divisors (see below), whose sum is σ = 71255360. Its totient is φ = 13160448.

The previous prime is 31443661. The next prime is 31443721. The reversal of 31443664 is 46634413.

It is a happy number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31443661) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1552 + ... + 8080.

It is an arithmetic number, because the mean of its divisors is an integer number (1781384).

Almost surely, 2^31443664 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 31443664, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (35627680).

31443664 is an abundant number, since it is smaller than the sum of its proper divisors (39811696).

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

31443664 is a wasteful number, since it uses less digits than its factorization.

31443664 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6587 (or 6581 counting only the distinct ones).

The product of its digits is 20736, while the sum is 31.

The square root of 31443664 is about 5607.4650244117. The cubic root of 31443664 is about 315.6295932279.

The spelling of 31443664 in words is "thirty-one million, four hundred forty-three thousand, six hundred sixty-four".