138059891 has 2 divisors, whose sum is σ = 138059892. Its totient is φ = 138059890.

The previous prime is 138059879. The next prime is 138059927. The reversal of 138059891 is 198950831.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-138059891 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (138059191) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 69029945 + 69029946.

It is an arithmetic number, because the mean of its divisors is an integer number (69029946).

Almost surely, 2^138059891 is an apocalyptic number.

138059891 is a deficient number, since it is larger than the sum of its proper divisors (1).

138059891 is an equidigital number, since it uses as much as digits as its factorization.

138059891 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 77760, while the sum is 44.

The square root of 138059891 is about 11749.8889781989. Note that the first 3 decimals coincide. The cubic root of 138059891 is about 516.8396718352.

The spelling of 138059891 in words is "one hundred thirty-eight million, fifty-nine thousand, eight hundred ninety-one".