18123257 has 2 divisors, whose sum is σ = 18123258. Its totient is φ = 18123256.

The previous prime is 18123223. The next prime is 18123263. The reversal of 18123257 is 75232181.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 13388281 + 4734976 = 3659^2 + 2176^2 .

It is a cyclic number.

It is not a de Polignac number, because 18123257 - 2¹⁴ = 18106873 is a prime.

It is equal to p_1158662 and since 18123257 and 1158662 have the same sum of digits, it is a Honaker prime.

It is not a weakly prime, because it can be changed into another prime (18123557) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9061628 + 9061629.

It is an arithmetic number, because the mean of its divisors is an integer number (9061629).

Almost surely, 2^18123257 is an apocalyptic number.

It is an amenable number.

18123257 is a deficient number, since it is larger than the sum of its proper divisors (1).

18123257 is an equidigital number, since it uses as much as digits as its factorization.

18123257 is an evil number, because the sum of its binary digits is even.

The product of its digits is 3360, while the sum is 29.

The square root of 18123257 is about 4257.1418815915. The cubic root of 18123257 is about 262.6709731215.

The spelling of 18123257 in words is "eighteen million, one hundred twenty-three thousand, two hundred fifty-seven".