31880628 has 126 divisors (see below), whose sum is σ = 93296294. Its totient is φ = 9471168.

The previous prime is 31880621. The next prime is 31880659. The reversal of 31880628 is 82608813.

It can be written as a sum of positive squares in 3 ways, for example, as 1542564 + 30338064 = 1242^2 + 5508^2 .

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 31880592 and 31880601.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31880621) by changing a digit.

It is a polite number, since it can be written in 41 ways as a sum of consecutive naturals, for example, 1099318 + ... + 1099346.

Almost surely, 2^31880628 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 31880628, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (46648147).

31880628 is an abundant number, since it is smaller than the sum of its proper divisors (61415666).

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

31880628 is a wasteful number, since it uses less digits than its factorization.

31880628 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 93 (or 47 counting only the distinct ones).

The product of its (nonzero) digits is 18432, while the sum is 36.

The square root of 31880628 is about 5646.2932973766. The cubic root of 31880628 is about 317.0849450762.

The spelling of 31880628 in words is "thirty-one million, eight hundred eighty thousand, six hundred twenty-eight".