31640113 has 4 divisors (see below), whose sum is σ = 31920228. Its totient is φ = 31360000.

The previous prime is 31640039. The next prime is 31640129. The reversal of 31640113 is 31104613.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 31104613 = 3527 ⋅8819.

It can be written as a sum of positive squares in 2 ways, for example, as 2663424 + 28976689 = 1632^2 + 5383^2 .

It is a cyclic number.

It is not a de Polignac number, because 31640113 - 2¹³ = 31631921 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (31640173) 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, 139888 + ... + 140113.

It is an arithmetic number, because the mean of its divisors is an integer number (7980057).

Almost surely, 2^31640113 is an apocalyptic number.

It is an amenable number.

31640113 is a deficient number, since it is larger than the sum of its proper divisors (280115).

31640113 is a wasteful number, since it uses less digits than its factorization.

31640113 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 280114.

The product of its (nonzero) digits is 216, while the sum is 19.

The square root of 31640113 is about 5624.9544887048. The cubic root of 31640113 is about 316.2855434542.

Adding to 31640113 its reverse (31104613), we get a palindrome (62744726).

The spelling of 31640113 in words is "thirty-one million, six hundred forty thousand, one hundred thirteen".