1338138257 has 2 divisors, whose sum is σ = 1338138258. Its totient is φ = 1338138256.

The previous prime is 1338138247. The next prime is 1338138259. The reversal of 1338138257 is 7528318331.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1257695296 + 80442961 = 35464^2 + 8969^2 .

It is a cyclic number.

It is not a de Polignac number, because 1338138257 - 2²⁶ = 1271029393 is a prime.

It is a super-2 number, since 2×1338138257² = 3581227989693996098, which contains 22 as substring.

Together with 1338138259, 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 (1338138259) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 669069128 + 669069129.

It is an arithmetic number, because the mean of its divisors is an integer number (669069129).

Almost surely, 2^1338138257 is an apocalyptic number.

It is an amenable number.

1338138257 is a deficient number, since it is larger than the sum of its proper divisors (1).

1338138257 is an equidigital number, since it uses as much as digits as its factorization.

1338138257 is an evil number, because the sum of its binary digits is even.

The product of its digits is 120960, while the sum is 41.

The square root of 1338138257 is about 36580.5721251049. The cubic root of 1338138257 is about 1101.9629569906.

The spelling of 1338138257 in words is "one billion, three hundred thirty-eight million, one hundred thirty-eight thousand, two hundred fifty-seven".