31825728 has 84 divisors (see below), whose sum is σ = 99535488. Its totient is φ = 9642240.

The previous prime is 31825727. The next prime is 31825753. The reversal of 31825728 is 82752813.

31825728 is a `hidden beast` number, since 3 + 1 + 82 + 572 + 8 = 666.

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 = 31825692 and 31825701.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31825727) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 3825 + ... + 8847.

Almost surely, 2^31825728 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 31825728, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (49767744).

31825728 is an abundant number, since it is smaller than the sum of its proper divisors (67709760).

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

31825728 is a wasteful number, since it uses less digits than its factorization.

31825728 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5052 (or 5039 counting only the distinct ones).

The product of its digits is 26880, while the sum is 36.

The square root of 31825728 is about 5641.4296060485. The cubic root of 31825728 is about 316.9028285726.

The spelling of 31825728 in words is "thirty-one million, eight hundred twenty-five thousand, seven hundred twenty-eight".