149555993 has 4 divisors (see below), whose sum is σ = 151788240. Its totient is φ = 147323748.

The previous prime is 149555981. The next prime is 149556037. The reversal of 149555993 is 399555941.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 149555993 - 2⁴ = 149555977 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (149555963) 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, 1116023 + ... + 1116156.

It is an arithmetic number, because the mean of its divisors is an integer number (37947060).

Almost surely, 2^149555993 is an apocalyptic number.

It is an amenable number.

149555993 is a deficient number, since it is larger than the sum of its proper divisors (2232247).

149555993 is an equidigital number, since it uses as much as digits as its factorization.

149555993 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2232246.

The product of its digits is 1093500, while the sum is 50.

The square root of 149555993 is about 12229.3087703271. The cubic root of 149555993 is about 530.8045133085.

The spelling of 149555993 in words is "one hundred forty-nine million, five hundred fifty-five thousand, nine hundred ninety-three".