149911891 has 2 divisors, whose sum is σ = 149911892. Its totient is φ = 149911890.

The previous prime is 149911859. The next prime is 149911969. The reversal of 149911891 is 198119941.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 149911891 - 2⁵ = 149911859 is a prime.

It is not a weakly prime, because it can be changed into another prime (149911591) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 74955945 + 74955946.

It is an arithmetic number, because the mean of its divisors is an integer number (74955946).

Almost surely, 2^149911891 is an apocalyptic number.

149911891 is a deficient number, since it is larger than the sum of its proper divisors (1).

149911891 is an equidigital number, since it uses as much as digits as its factorization.

149911891 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 23328, while the sum is 43.

The square root of 149911891 is about 12243.8511506797. The cubic root of 149911891 is about 531.2252311220.

The spelling of 149911891 in words is "one hundred forty-nine million, nine hundred eleven thousand, eight hundred ninety-one".