42165666565 has 16 divisors (see below), whose sum is σ = 55233674496. Its totient is φ = 30646504000.

The previous prime is 42165666553. The next prime is 42165666601. The reversal of 42165666565 is 56566656124.

It is not a de Polignac number, because 42165666565 - 2¹⁹ = 42165142277 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 155086 + ... + 329215.

It is an arithmetic number, because the mean of its divisors is an integer number (3452104656).

Almost surely, 2^42165666565 is an apocalyptic number.

It is an amenable number.

42165666565 is a deficient number, since it is larger than the sum of its proper divisors (13068007931).

42165666565 is a wasteful number, since it uses less digits than its factorization.

42165666565 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 485900.

The product of its digits is 7776000, while the sum is 52.

The spelling of 42165666565 in words is "forty-two billion, one hundred sixty-five million, six hundred sixty-six thousand, five hundred sixty-five".