31157680 has 40 divisors (see below), whose sum is σ = 73535472. Its totient is φ = 12274944.

The previous prime is 31157677. The next prime is 31157681. The reversal of 31157680 is 8675113.

It is a tau number, because it is divible by the number of its divisors (40).

It is not an unprimeable number, because it can be changed into a prime (31157681) 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, 2454 + ... + 8266.

Almost surely, 2^31157680 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 31157680, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (36767736).

31157680 is an abundant number, since it is smaller than the sum of its proper divisors (42377792).

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

31157680 is a wasteful number, since it uses less digits than its factorization.

31157680 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5893 (or 5887 counting only the distinct ones).

The product of its (nonzero) digits is 5040, while the sum is 31.

The square root of 31157680 is about 5581.9064843474. The cubic root of 31157680 is about 314.6697807633.

The spelling of 31157680 in words is "thirty-one million, one hundred fifty-seven thousand, six hundred eighty".