149787521 has 4 divisors (see below), whose sum is σ = 161309652. Its totient is φ = 138265392.

The previous prime is 149787511. The next prime is 149787551. The reversal of 149787521 is 125787941.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 93702400 + 56085121 = 9680^2 + 7489^2 .

It is a cyclic number.

It is not a de Polignac number, because 149787521 - 2⁶ = 149787457 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (149787511) 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 3 ways as a sum of consecutive naturals, for example, 5761046 + ... + 5761071.

It is an arithmetic number, because the mean of its divisors is an integer number (40327413).

Almost surely, 2^149787521 is an apocalyptic number.

It is an amenable number.

149787521 is a deficient number, since it is larger than the sum of its proper divisors (11522131).

149787521 is a wasteful number, since it uses less digits than its factorization.

149787521 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11522130.

The product of its digits is 141120, while the sum is 44.

The square root of 149787521 is about 12238.7712210009. The cubic root of 149787521 is about 531.0782853381.

The spelling of 149787521 in words is "one hundred forty-nine million, seven hundred eighty-seven thousand, five hundred twenty-one".