138169457 has 2 divisors, whose sum is σ = 138169458. Its totient is φ = 138169456.

The previous prime is 138169411. The next prime is 138169459. The reversal of 138169457 is 754961831.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 134003776 + 4165681 = 11576^2 + 2041^2 .

It is a cyclic number.

It is not a de Polignac number, because 138169457 - 2⁶ = 138169393 is a prime.

Together with 138169459, 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 (138169459) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 69084728 + 69084729.

It is an arithmetic number, because the mean of its divisors is an integer number (69084729).

Almost surely, 2^138169457 is an apocalyptic number.

It is an amenable number.

138169457 is a deficient number, since it is larger than the sum of its proper divisors (1).

138169457 is an equidigital number, since it uses as much as digits as its factorization.

138169457 is an evil number, because the sum of its binary digits is even.

The product of its digits is 181440, while the sum is 44.

The square root of 138169457 is about 11754.5504805586. The cubic root of 138169457 is about 516.9763590884.

The spelling of 138169457 in words is "one hundred thirty-eight million, one hundred sixty-nine thousand, four hundred fifty-seven".