149555991 has 16 divisors (see below), whose sum is σ = 215115264. Its totient is φ = 91876704.

The previous prime is 149555981. The next prime is 149556037. The reversal of 149555991 is 199555941.

It is not a de Polignac number, because 149555991 - 2¹³ = 149547799 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 149555991.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (149555921) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 22270 + ... + 28196.

It is an arithmetic number, because the mean of its divisors is an integer number (13444704).

Almost surely, 2^149555991 is an apocalyptic number.

149555991 is a deficient number, since it is larger than the sum of its proper divisors (65559273).

149555991 is a wasteful number, since it uses less digits than its factorization.

149555991 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6590.

The product of its digits is 364500, while the sum is 48.

The square root of 149555991 is about 12229.3086885564. The cubic root of 149555991 is about 530.8045109423.

The spelling of 149555991 in words is "one hundred forty-nine million, five hundred fifty-five thousand, nine hundred ninety-one".