155000191 has 4 divisors (see below), whose sum is σ = 155787192. Its totient is φ = 154213192.

The previous prime is 155000189. The next prime is 155000201. The reversal of 155000191 is 191000551.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 191000551 = 7 ⋅27285793.

It is a cyclic number.

It is not a de Polignac number, because 155000191 - 2¹ = 155000189 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (155000161) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 393205 + ... + 393598.

It is an arithmetic number, because the mean of its divisors is an integer number (38946798).

Almost surely, 2^155000191 is an apocalyptic number.

155000191 is a deficient number, since it is larger than the sum of its proper divisors (787001).

155000191 is an equidigital number, since it uses as much as digits as its factorization.

155000191 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 787000.

The product of its (nonzero) digits is 225, while the sum is 22.

The square root of 155000191 is about 12449.9072687310. The cubic root of 155000191 is about 537.1687561378.

The spelling of 155000191 in words is "one hundred fifty-five million, one hundred ninety-one", and thus it is an aban number.