149921509 has 4 divisors (see below), whose sum is σ = 151066080. Its totient is φ = 148776940.

The previous prime is 149921467. The next prime is 149921557. The reversal of 149921509 is 905129941.

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 149921509 - 2⁹ = 149920997 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 (149921599) 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, 572089 + ... + 572350.

It is an arithmetic number, because the mean of its divisors is an integer number (37766520).

Almost surely, 2^149921509 is an apocalyptic number.

It is an amenable number.

149921509 is a deficient number, since it is larger than the sum of its proper divisors (1144571).

149921509 is a wasteful number, since it uses less digits than its factorization.

149921509 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1144570.

The product of its (nonzero) digits is 29160, while the sum is 40.

The square root of 149921509 is about 12244.2439129576. The cubic root of 149921509 is about 531.2365916062.

The spelling of 149921509 in words is "one hundred forty-nine million, nine hundred twenty-one thousand, five hundred nine".