139057991 has 2 divisors, whose sum is σ = 139057992. Its totient is φ = 139057990.

The previous prime is 139057969. The next prime is 139058009. The reversal of 139057991 is 199750931.

139057991 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 139057991 - 2¹⁴ = 139041607 is a prime.

It is a Sophie Germain prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (139057591) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 69528995 + 69528996.

It is an arithmetic number, because the mean of its divisors is an integer number (69528996).

Almost surely, 2^139057991 is an apocalyptic number.

139057991 is a deficient number, since it is larger than the sum of its proper divisors (1).

139057991 is an equidigital number, since it uses as much as digits as its factorization.

139057991 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 76545, while the sum is 44.

The square root of 139057991 is about 11792.2852323034. The cubic root of 139057991 is about 518.0821749151.

The spelling of 139057991 in words is "one hundred thirty-nine million, fifty-seven thousand, nine hundred ninety-one".