18284257 has 2 divisors, whose sum is σ = 18284258. Its totient is φ = 18284256.

The previous prime is 18284219. The next prime is 18284261. The reversal of 18284257 is 75248281.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 18284176 + 81 = 4276^2 + 9^2 .

It is an emirp because it is prime and its reverse (75248281) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-18284257 is a prime.

It is not a weakly prime, because it can be changed into another prime (18284557) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9142128 + 9142129.

It is an arithmetic number, because the mean of its divisors is an integer number (9142129).

Almost surely, 2^18284257 is an apocalyptic number.

It is an amenable number.

18284257 is a deficient number, since it is larger than the sum of its proper divisors (1).

18284257 is an equidigital number, since it uses as much as digits as its factorization.

18284257 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 35840, while the sum is 37.

The square root of 18284257 is about 4276.0094714582. The cubic root of 18284257 is about 263.4465035477.

The spelling of 18284257 in words is "eighteen million, two hundred eighty-four thousand, two hundred fifty-seven".