42125809 has 8 divisors (see below), whose sum is σ = 46006560. Its totient is φ = 38253600.

The previous prime is 42125789. The next prime is 42125821. The reversal of 42125809 is 90852124.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 42125809 - 2⁹ = 42125297 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (42125899) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 12694 + ... + 15664.

It is an arithmetic number, because the mean of its divisors is an integer number (5750820).

Almost surely, 2^42125809 is an apocalyptic number.

It is an amenable number.

42125809 is a deficient number, since it is larger than the sum of its proper divisors (3880751).

42125809 is a wasteful number, since it uses less digits than its factorization.

42125809 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4271.

The product of its (nonzero) digits is 5760, while the sum is 31.

The square root of 42125809 is about 6490.4398156057. The cubic root of 42125809 is about 347.9493942576.

The spelling of 42125809 in words is "forty-two million, one hundred twenty-five thousand, eight hundred nine".