18242557 has 2 divisors, whose sum is σ = 18242558. Its totient is φ = 18242556.

The previous prime is 18242551. The next prime is 18242561. The reversal of 18242557 is 75524281.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 18156121 + 86436 = 4261^2 + 294^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-18242557 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (18242551) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9121278 + 9121279.

It is an arithmetic number, because the mean of its divisors is an integer number (9121279).

Almost surely, 2^18242557 is an apocalyptic number.

It is an amenable number.

18242557 is a deficient number, since it is larger than the sum of its proper divisors (1).

18242557 is an equidigital number, since it uses as much as digits as its factorization.

18242557 is an evil number, because the sum of its binary digits is even.

The product of its digits is 22400, while the sum is 34.

The square root of 18242557 is about 4271.1306465619. The cubic root of 18242557 is about 263.2460746336.

The spelling of 18242557 in words is "eighteen million, two hundred forty-two thousand, five hundred fifty-seven".