18291313 has 2 divisors, whose sum is σ = 18291314. Its totient is φ = 18291312.

The previous prime is 18291311. The next prime is 18291347. The reversal of 18291313 is 31319281.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 16136289 + 2155024 = 4017^2 + 1468^2 .

It is a cyclic number.

It is not a de Polignac number, because 18291313 - 2¹ = 18291311 is a prime.

Together with 18291311, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (18291311) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9145656 + 9145657.

It is an arithmetic number, because the mean of its divisors is an integer number (9145657).

Almost surely, 2^18291313 is an apocalyptic number.

It is an amenable number.

18291313 is a deficient number, since it is larger than the sum of its proper divisors (1).

18291313 is an equidigital number, since it uses as much as digits as its factorization.

18291313 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1296, while the sum is 28.

The square root of 18291313 is about 4276.8344602054. The cubic root of 18291313 is about 263.4803876966.

The spelling of 18291313 in words is "eighteen million, two hundred ninety-one thousand, three hundred thirteen".