1998257 has 2 divisors, whose sum is σ = 1998258. Its totient is φ = 1998256.

The previous prime is 1998251. The next prime is 1998277. The reversal of 1998257 is 7528991.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1825201 + 173056 = 1351^2 + 416^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1998257 is a prime.

It is not a weakly prime, because it can be changed into another prime (1998251) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 999128 + 999129.

It is an arithmetic number, because the mean of its divisors is an integer number (999129).

2^1998257 is an apocalyptic number.

It is an amenable number.

1998257 is a deficient number, since it is larger than the sum of its proper divisors (1).

1998257 is an equidigital number, since it uses as much as digits as its factorization.

1998257 is an evil number, because the sum of its binary digits is even.

The product of its digits is 45360, while the sum is 41.

The square root of 1998257 is about 1413.5971844907. The cubic root of 1998257 is about 125.9554936453.

The spelling of 1998257 in words is "one million, nine hundred ninety-eight thousand, two hundred fifty-seven".