139891187 has 2 divisors, whose sum is σ = 139891188. Its totient is φ = 139891186.

The previous prime is 139891151. The next prime is 139891207. The reversal of 139891187 is 781198931.

139891187 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 139891187 - 2⁶ = 139891123 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (139891387) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 69945593 + 69945594.

It is an arithmetic number, because the mean of its divisors is an integer number (69945594).

Almost surely, 2^139891187 is an apocalyptic number.

139891187 is a deficient number, since it is larger than the sum of its proper divisors (1).

139891187 is an equidigital number, since it uses as much as digits as its factorization.

139891187 is an evil number, because the sum of its binary digits is even.

The product of its digits is 108864, while the sum is 47.

The square root of 139891187 is about 11827.5604838868. The cubic root of 139891187 is about 519.1148489217.

The spelling of 139891187 in words is "one hundred thirty-nine million, eight hundred ninety-one thousand, one hundred eighty-seven".