138193457 has 2 divisors, whose sum is σ = 138193458. Its totient is φ = 138193456.

The previous prime is 138193421. The next prime is 138193507. The reversal of 138193457 is 754391831.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 105657841 + 32535616 = 10279^2 + 5704^2 .

It is a cyclic number.

It is not a de Polignac number, because 138193457 - 2¹⁰ = 138192433 is a prime.

It is a super-2 number, since 2×138193457² = 38194863115221698, which contains 22 as substring.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (138193057) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 69096728 + 69096729.

It is an arithmetic number, because the mean of its divisors is an integer number (69096729).

Almost surely, 2^138193457 is an apocalyptic number.

It is an amenable number.

138193457 is a deficient number, since it is larger than the sum of its proper divisors (1).

138193457 is an equidigital number, since it uses as much as digits as its factorization.

138193457 is an evil number, because the sum of its binary digits is even.

The product of its digits is 90720, while the sum is 41.

The square root of 138193457 is about 11755.5713174648. The cubic root of 138193457 is about 517.0062902434.

The spelling of 138193457 in words is "one hundred thirty-eight million, one hundred ninety-three thousand, four hundred fifty-seven".