138172757 has 2 divisors, whose sum is σ = 138172758. Its totient is φ = 138172756.

The previous prime is 138172751. The next prime is 138172759. The reversal of 138172757 is 757271831.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 110019121 + 28153636 = 10489^2 + 5306^2 .

It is a cyclic number.

It is not a de Polignac number, because 138172757 - 2¹² = 138168661 is a prime.

Together with 138172759, it forms a pair of twin primes.

It is a Chen prime.

It is equal to p_7814696 and since 138172757 and 7814696 have the same sum of digits, it is a Honaker prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (138172751) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 69086378 + 69086379.

It is an arithmetic number, because the mean of its divisors is an integer number (69086379).

Almost surely, 2^138172757 is an apocalyptic number.

It is an amenable number.

138172757 is a deficient number, since it is larger than the sum of its proper divisors (1).

138172757 is an equidigital number, since it uses as much as digits as its factorization.

138172757 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 82320, while the sum is 41.

The square root of 138172757 is about 11754.6908508901. The cubic root of 138172757 is about 516.9804748278.

The spelling of 138172757 in words is "one hundred thirty-eight million, one hundred seventy-two thousand, seven hundred fifty-seven".