42523209 has 6 divisors (see below), whose sum is σ = 61422426. Its totient is φ = 28348800.

The previous prime is 42523181. The next prime is 42523211. The reversal of 42523209 is 90232524.

42523209 is a `hidden beast` number, since 425 + 232 + 0 + 9 = 666.

It can be written as a sum of positive squares in only one way, i.e., 29127609 + 13395600 = 5397^2 + 3660^2 .

It is not a de Polignac number, because 42523209 - 2⁵ = 42523177 is a prime.

It is not an unprimeable number, because it can be changed into a prime (42523219) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 2362392 + ... + 2362409.

It is an arithmetic number, because the mean of its divisors is an integer number (10237071).

Almost surely, 2^42523209 is an apocalyptic number.

It is an amenable number.

42523209 is a deficient number, since it is larger than the sum of its proper divisors (18899217).

42523209 is a wasteful number, since it uses less digits than its factorization.

42523209 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4724807 (or 4724804 counting only the distinct ones).

The product of its (nonzero) digits is 4320, while the sum is 27.

The square root of 42523209 is about 6520.9822112930. The cubic root of 42523209 is about 349.0401154754.

The spelling of 42523209 in words is "forty-two million, five hundred twenty-three thousand, two hundred nine".