31691349 has 24 divisors (see below), whose sum is σ = 48964032. Its totient is φ = 19681920.

The previous prime is 31691329. The next prime is 31691353. The reversal of 31691349 is 94319613.

It is not a de Polignac number, because 31691349 - 2²¹ = 29594197 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31691329) 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 23 ways as a sum of consecutive naturals, for example, 14754 + ... + 16764.

It is an arithmetic number, because the mean of its divisors is an integer number (2040168).

Almost surely, 2^31691349 is an apocalyptic number.

It is an amenable number.

31691349 is a deficient number, since it is larger than the sum of its proper divisors (17272683).

31691349 is a wasteful number, since it uses less digits than its factorization.

31691349 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2137 (or 2134 counting only the distinct ones).

The product of its digits is 17496, while the sum is 36.

The square root of 31691349 is about 5629.5069944001. The cubic root of 31691349 is about 316.4561756591.

The spelling of 31691349 in words is "thirty-one million, six hundred ninety-one thousand, three hundred forty-nine".