18724313 has 2 divisors, whose sum is σ = 18724314. Its totient is φ = 18724312.

The previous prime is 18724301. The next prime is 18724337. The reversal of 18724313 is 31342781.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 18079504 + 644809 = 4252^2 + 803^2 .

It is a cyclic number.

It is not a de Polignac number, because 18724313 - 2⁴ = 18724297 is a prime.

It is a Sophie Germain prime.

It is a Chen prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (18724373) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9362156 + 9362157.

It is an arithmetic number, because the mean of its divisors is an integer number (9362157).

Almost surely, 2^18724313 is an apocalyptic number.

It is an amenable number.

18724313 is a deficient number, since it is larger than the sum of its proper divisors (1).

18724313 is an equidigital number, since it uses as much as digits as its factorization.

18724313 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 4032, while the sum is 29.

The square root of 18724313 is about 4327.1599230904. The cubic root of 18724313 is about 265.5432690275.

The spelling of 18724313 in words is "eighteen million, seven hundred twenty-four thousand, three hundred thirteen".