138424457 has 2 divisors, whose sum is σ = 138424458. Its totient is φ = 138424456.

The previous prime is 138424423. The next prime is 138424469. The reversal of 138424457 is 754424831.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 138391696 + 32761 = 11764^2 + 181^2 .

It is a cyclic number.

It is not a de Polignac number, because 138424457 - 2¹⁰ = 138423433 is a prime.

It is a super-2 number, since 2×138424457² = 38322660591489698, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 138424457.

It is not a weakly prime, because it can be changed into another prime (138424417) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 69212228 + 69212229.

It is an arithmetic number, because the mean of its divisors is an integer number (69212229).

Almost surely, 2^138424457 is an apocalyptic number.

It is an amenable number.

138424457 is a deficient number, since it is larger than the sum of its proper divisors (1).

138424457 is an equidigital number, since it uses as much as digits as its factorization.

138424457 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 107520, while the sum is 38.

The square root of 138424457 is about 11765.3923436492. The cubic root of 138424457 is about 517.2942005711.

The spelling of 138424457 in words is "one hundred thirty-eight million, four hundred twenty-four thousand, four hundred fifty-seven".