139870091 has 2 divisors, whose sum is σ = 139870092. Its totient is φ = 139870090.

The previous prime is 139870043. The next prime is 139870097. The reversal of 139870091 is 190078931.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-139870091 is a prime.

It is not a weakly prime, because it can be changed into another prime (139870097) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 69935045 + 69935046.

It is an arithmetic number, because the mean of its divisors is an integer number (69935046).

Almost surely, 2^139870091 is an apocalyptic number.

139870091 is a deficient number, since it is larger than the sum of its proper divisors (1).

139870091 is an equidigital number, since it uses as much as digits as its factorization.

139870091 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 13608, while the sum is 38.

The square root of 139870091 is about 11826.6686349115. The cubic root of 139870091 is about 519.0887529309.

The spelling of 139870091 in words is "one hundred thirty-nine million, eight hundred seventy thousand, ninety-one".