31689408 has 28 divisors (see below), whose sum is σ = 83845400. Its totient is φ = 10563072.

The previous prime is 31689407. The next prime is 31689443. The reversal of 31689408 is 80498613.

31689408 is nontrivially palindromic in base 5.

It is not an unprimeable number, because it can be changed into a prime (31689403) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 82333 + ... + 82716.

Almost surely, 2^31689408 is an apocalyptic number.

It is an amenable number.

31689408 is an abundant number, since it is smaller than the sum of its proper divisors (52155992).

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

31689408 is a wasteful number, since it uses less digits than its factorization.

31689408 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 165064 (or 165054 counting only the distinct ones).

The product of its (nonzero) digits is 41472, while the sum is 39.

The square root of 31689408 is about 5629.3345965576. The cubic root of 31689408 is about 316.4497148636.

The spelling of 31689408 in words is "thirty-one million, six hundred eighty-nine thousand, four hundred eight".