31348813 has 2 divisors, whose sum is σ = 31348814. Its totient is φ = 31348812.

The previous prime is 31348789. The next prime is 31348819. The reversal of 31348813 is 31884313.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 21501769 + 9847044 = 4637^2 + 3138^2 .

It is an emirp because it is prime and its reverse (31884313) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 31348813 - 2²¹ = 29251661 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (31348819) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15674406 + 15674407.

It is an arithmetic number, because the mean of its divisors is an integer number (15674407).

Almost surely, 2^31348813 is an apocalyptic number.

It is an amenable number.

31348813 is a deficient number, since it is larger than the sum of its proper divisors (1).

31348813 is an equidigital number, since it uses as much as digits as its factorization.

31348813 is an evil number, because the sum of its binary digits is even.

The product of its digits is 6912, while the sum is 31.

The square root of 31348813 is about 5599.0010716198. The cubic root of 31348813 is about 315.3119040435.

The spelling of 31348813 in words is "thirty-one million, three hundred forty-eight thousand, eight hundred thirteen".