188145009 has 24 divisors (see below), whose sum is σ = 295375080. Its totient is φ = 114711552.

The previous prime is 188145007. The next prime is 188145019. The reversal of 188145009 is 900541881.

It can be written as a sum of positive squares in 4 ways, for example, as 15800625 + 172344384 = 3975^2 + 13128^2 .

It is not a de Polignac number, because 188145009 - 2¹ = 188145007 is a prime.

It is a super-2 number, since 2×188145009² = 70797088823220162, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (188145007) 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 in 23 ways as a sum of consecutive naturals, for example, 5377 + ... + 20129.

It is an arithmetic number, because the mean of its divisors is an integer number (12307295).

Almost surely, 2^188145009 is an apocalyptic number.

It is an amenable number.

188145009 is a deficient number, since it is larger than the sum of its proper divisors (107230071).

188145009 is a wasteful number, since it uses less digits than its factorization.

188145009 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14881 (or 14878 counting only the distinct ones).

The product of its (nonzero) digits is 11520, while the sum is 36.

The square root of 188145009 is about 13716.5961156549. The cubic root of 188145009 is about 573.0126821202.

The spelling of 188145009 in words is "one hundred eighty-eight million, one hundred forty-five thousand, nine".