31881696 has 192 divisors, whose sum is σ = 110315520. Its totient is φ = 7810560.

The previous prime is 31881683. The next prime is 31881697. The reversal of 31881696 is 69618813.

It is a Harshad number since it is a multiple of its sum of digits (42).

It is a zygodrome in base 2.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31881697) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 140335 + ... + 140561.

It is an arithmetic number, because the mean of its divisors is an integer number (574560).

Almost surely, 2^31881696 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 31881696, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (55157760).

31881696 is an abundant number, since it is smaller than the sum of its proper divisors (78433824).

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

31881696 is a wasteful number, since it uses less digits than its factorization.

31881696 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 277 (or 269 counting only the distinct ones).

The product of its digits is 62208, while the sum is 42.

The square root of 31881696 is about 5646.3878719054. The cubic root of 31881696 is about 317.0884858151.

It can be divided in two parts, 3188 and 1696, that added together give a palindrome (4884).

The spelling of 31881696 in words is "thirty-one million, eight hundred eighty-one thousand, six hundred ninety-six".