31640129 has 2 divisors, whose sum is σ = 31640130. Its totient is φ = 31640128.

The previous prime is 31640039. The next prime is 31640137. The reversal of 31640129 is 92104613.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 31080625 + 559504 = 5575^2 + 748^2 .

It is an emirp because it is prime and its reverse (92104613) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 31640129 - 2²⁰ = 30591553 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 31640098 and 31640107.

It is not a weakly prime, because it can be changed into another prime (31640929) 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 as a sum of consecutive naturals, namely, 15820064 + 15820065.

It is an arithmetic number, because the mean of its divisors is an integer number (15820065).

Almost surely, 2^31640129 is an apocalyptic number.

It is an amenable number.

31640129 is a deficient number, since it is larger than the sum of its proper divisors (1).

31640129 is an equidigital number, since it uses as much as digits as its factorization.

31640129 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1296, while the sum is 26.

The square root of 31640129 is about 5624.9559109383. The cubic root of 31640129 is about 316.2855967680.

The spelling of 31640129 in words is "thirty-one million, six hundred forty thousand, one hundred twenty-nine".