42166525561 has 16 divisors (see below), whose sum is σ = 44822937600. Its totient is φ = 39555345168.

The previous prime is 42166525549. The next prime is 42166525589. The reversal of 42166525561 is 16552566124.

42166525561 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 42166525561 - 2³³ = 33576590969 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (42166525361) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 990660 + ... + 1032346.

It is an arithmetic number, because the mean of its divisors is an integer number (2801433600).

Almost surely, 2^42166525561 is an apocalyptic number.

It is an amenable number.

42166525561 is a deficient number, since it is larger than the sum of its proper divisors (2656412039).

42166525561 is a wasteful number, since it uses less digits than its factorization.

42166525561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 42228.

The product of its digits is 432000, while the sum is 43.

The spelling of 42166525561 in words is "forty-two billion, one hundred sixty-six million, five hundred twenty-five thousand, five hundred sixty-one".