42166523565 has 20 divisors (see below), whose sum is σ = 75587398524. Its totient is φ = 22488812352.

The previous prime is 42166523557. The next prime is 42166523593. The reversal of 42166523565 is 56532566124.

42166523565 is a `hidden beast` number, since 4 + 2 + 1 + 6 + 65 + 23 + 565 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 7733267721 + 34433255844 = 87939^2 + 185562^2 .

It is not a de Polignac number, because 42166523565 - 2³ = 42166523557 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a self number, because there is not a number n which added to its sum of digits gives 42166523565.

It is a congruent number.

It is an unprimeable number.

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 19 ways as a sum of consecutive naturals, for example, 52057032 + ... + 52057841.

Almost surely, 2^42166523565 is an apocalyptic number.

42166523565 is a gapful number since it is divisible by the number (45) formed by its first and last digit.

It is an amenable number.

42166523565 is a deficient number, since it is larger than the sum of its proper divisors (33420874959).

42166523565 is a wasteful number, since it uses less digits than its factorization.

42166523565 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 104114890 (or 104114881 counting only the distinct ones).

The product of its digits is 1296000, while the sum is 45.

The spelling of 42166523565 in words is "forty-two billion, one hundred sixty-six million, five hundred twenty-three thousand, five hundred sixty-five".