100400257 has 2 divisors, whose sum is σ = 100400258. Its totient is φ = 100400256.

The previous prime is 100400207. The next prime is 100400273. The reversal of 100400257 is 752004001.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 71927361 + 28472896 = 8481^2 + 5336^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-100400257 is a prime.

It is not a weakly prime, because it can be changed into another prime (100400207) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 50200128 + 50200129.

It is an arithmetic number, because the mean of its divisors is an integer number (50200129).

Almost surely, 2^100400257 is an apocalyptic number.

It is an amenable number.

100400257 is a deficient number, since it is larger than the sum of its proper divisors (1).

100400257 is an equidigital number, since it uses as much as digits as its factorization.

100400257 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 280, while the sum is 19.

The square root of 100400257 is about 10019.9928642689. The cubic root of 100400257 is about 464.7773351022. Note that the first 3 decimals are identical.

Adding to 100400257 its reverse (752004001), we get a palindrome (852404258).

The spelling of 100400257 in words is "one hundred million, four hundred thousand, two hundred fifty-seven".