31328256 has 48 divisors (see below), whose sum is σ = 83538000. Its totient is φ = 10440704.

The previous prime is 31328249. The next prime is 31328261. The reversal of 31328256 is 65282313.

It is a tau number, because it is divible by the number of its divisors (48).

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3595 + ... + 8693.

It is an arithmetic number, because the mean of its divisors is an integer number (1740375).

Almost surely, 2^31328256 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 31328256, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (41769000).

31328256 is an abundant number, since it is smaller than the sum of its proper divisors (52209744).

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

31328256 is an equidigital number, since it uses as much as digits as its factorization.

31328256 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5124 (or 5104 counting only the distinct ones).

The product of its digits is 8640, while the sum is 30.

The square root of 31328256 is about 5597.1649966747. The cubic root of 31328256 is about 315.2429669926.

The spelling of 31328256 in words is "thirty-one million, three hundred twenty-eight thousand, two hundred fifty-six".