138495691 has 2 divisors, whose sum is σ = 138495692. Its totient is φ = 138495690.

The previous prime is 138495683. The next prime is 138495697. The reversal of 138495691 is 196594831.

It is a strong prime.

It is an emirp because it is prime and its reverse (196594831) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 138495691 - 2³ = 138495683 is a prime.

It is not a weakly prime, because it can be changed into another prime (138495697) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 69247845 + 69247846.

It is an arithmetic number, because the mean of its divisors is an integer number (69247846).

Almost surely, 2^138495691 is an apocalyptic number.

138495691 is the 6795-th hex number.

138495691 is a deficient number, since it is larger than the sum of its proper divisors (1).

138495691 is an equidigital number, since it uses as much as digits as its factorization.

138495691 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 233280, while the sum is 46.

The square root of 138495691 is about 11768.4192226484. The cubic root of 138495691 is about 517.3829195176.

The spelling of 138495691 in words is "one hundred thirty-eight million, four hundred ninety-five thousand, six hundred ninety-one".