31440768 has 64 divisors (see below), whose sum is σ = 85594320. Its totient is φ = 10219520.

The previous prime is 31440757. The next prime is 31440811. The reversal of 31440768 is 86704413.

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, 14746 + ... + 16742.

Almost surely, 2^31440768 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 31440768, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (42797160).

31440768 is an abundant number, since it is smaller than the sum of its proper divisors (54153552).

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

31440768 is a wasteful number, since it uses less digits than its factorization.

31440768 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2055 (or 2043 counting only the distinct ones).

The product of its (nonzero) digits is 16128, while the sum is 33.

The square root of 31440768 is about 5607.2067912643. The cubic root of 31440768 is about 315.6199029729.

The spelling of 31440768 in words is "thirty-one million, four hundred forty thousand, seven hundred sixty-eight".