31129013 has 2 divisors, whose sum is σ = 31129014. Its totient is φ = 31129012.

The previous prime is 31129009. The next prime is 31129039. The reversal of 31129013 is 31092113.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 21003889 + 10125124 = 4583^2 + 3182^2 .

It is a cyclic number.

It is not a de Polignac number, because 31129013 - 2² = 31129009 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (31129213) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15564506 + 15564507.

It is an arithmetic number, because the mean of its divisors is an integer number (15564507).

Almost surely, 2^31129013 is an apocalyptic number.

It is an amenable number.

31129013 is a deficient number, since it is larger than the sum of its proper divisors (1).

31129013 is an equidigital number, since it uses as much as digits as its factorization.

31129013 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 162, while the sum is 20.

The square root of 31129013 is about 5579.3380431732. The cubic root of 31129013 is about 314.5732459065.

The spelling of 31129013 in words is "thirty-one million, one hundred twenty-nine thousand, thirteen".