1138197257 has 2 divisors, whose sum is σ = 1138197258. Its totient is φ = 1138197256.

The previous prime is 1138197253. The next prime is 1138197259. The reversal of 1138197257 is 7527918311.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1132726336 + 5470921 = 33656^2 + 2339^2 .

It is a cyclic number.

It is not a de Polignac number, because 1138197257 - 2² = 1138197253 is a prime.

Together with 1138197259, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (1138197253) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 569098628 + 569098629.

It is an arithmetic number, because the mean of its divisors is an integer number (569098629).

Almost surely, 2^1138197257 is an apocalyptic number.

It is an amenable number.

1138197257 is a deficient number, since it is larger than the sum of its proper divisors (1).

1138197257 is an equidigital number, since it uses as much as digits as its factorization.

1138197257 is an evil number, because the sum of its binary digits is even.

The product of its digits is 105840, while the sum is 44.

The square root of 1138197257 is about 33737.1791500119. The cubic root of 1138197257 is about 1044.0929858630.

The spelling of 1138197257 in words is "one billion, one hundred thirty-eight million, one hundred ninety-seven thousand, two hundred fifty-seven".