155900191 has 2 divisors, whose sum is σ = 155900192. Its totient is φ = 155900190.

The previous prime is 155900137. The next prime is 155900197. The reversal of 155900191 is 191009551.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 155900191 - 2¹⁵ = 155867423 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (155900197) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 77950095 + 77950096.

It is an arithmetic number, because the mean of its divisors is an integer number (77950096).

Almost surely, 2^155900191 is an apocalyptic number.

155900191 is a deficient number, since it is larger than the sum of its proper divisors (1).

155900191 is an equidigital number, since it uses as much as digits as its factorization.

155900191 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 2025, while the sum is 31.

The square root of 155900191 is about 12485.9997997757. Note that the first 3 decimals coincide. The cubic root of 155900191 is about 538.2064305046.

The spelling of 155900191 in words is "one hundred fifty-five million, nine hundred thousand, one hundred ninety-one".