31681394 has 8 divisors (see below), whose sum is σ = 47642988. Its totient is φ = 15800400.

The previous prime is 31681393. The next prime is 31681457. The reversal of 31681394 is 49318613.

It can be written as a sum of positive squares in 2 ways, for example, as 30393169 + 1288225 = 5513^2 + 1135^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is not an unprimeable number, because it can be changed into a prime (31681393) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 19157 + ... + 20744.

Almost surely, 2^31681394 is an apocalyptic number.

31681394 is a deficient number, since it is larger than the sum of its proper divisors (15961594).

31681394 is a wasteful number, since it uses less digits than its factorization.

31681394 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 40300.

The product of its digits is 15552, while the sum is 35.

The square root of 31681394 is about 5628.6227445086. The cubic root of 31681394 is about 316.4230367400.

The spelling of 31681394 in words is "thirty-one million, six hundred eighty-one thousand, three hundred ninety-four".