31681117 has 4 divisors (see below), whose sum is σ = 34118140. Its totient is φ = 29244096.

The previous prime is 31681103. The next prime is 31681127. The reversal of 31681117 is 71118613.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 71118613 = 1163 ⋅61151.

It can be written as a sum of positive squares in 2 ways, for example, as 4024036 + 27657081 = 2006^2 + 5259^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-31681117 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31681127) 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, 1218492 + ... + 1218517.

It is an arithmetic number, because the mean of its divisors is an integer number (8529535).

Almost surely, 2^31681117 is an apocalyptic number.

It is an amenable number.

31681117 is a deficient number, since it is larger than the sum of its proper divisors (2437023).

31681117 is a wasteful number, since it uses less digits than its factorization.

31681117 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2437022.

The product of its digits is 1008, while the sum is 28.

The square root of 31681117 is about 5628.5981380802. The cubic root of 31681117 is about 316.4221145433.

The spelling of 31681117 in words is "thirty-one million, six hundred eighty-one thousand, one hundred seventeen".