138374491 has 2 divisors, whose sum is σ = 138374492. Its totient is φ = 138374490.

The previous prime is 138374479. The next prime is 138374507. The reversal of 138374491 is 194473831.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 138374491 - 2⁵ = 138374459 is a prime.

It is not a weakly prime, because it can be changed into another prime (138374461) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 69187245 + 69187246.

It is an arithmetic number, because the mean of its divisors is an integer number (69187246).

Almost surely, 2^138374491 is an apocalyptic number.

138374491 is a deficient number, since it is larger than the sum of its proper divisors (1).

138374491 is an equidigital number, since it uses as much as digits as its factorization.

138374491 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 72576, while the sum is 40.

The square root of 138374491 is about 11763.2687208956. The cubic root of 138374491 is about 517.2319518588.

The spelling of 138374491 in words is "one hundred thirty-eight million, three hundred seventy-four thousand, four hundred ninety-one".