42165554657 has 4 divisors (see below), whose sum is σ = 42172744980. Its totient is φ = 42158364336.

The previous prime is 42165554579. The next prime is 42165554723. The reversal of 42165554657 is 75645556124.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 25905224401 + 16260330256 = 160951^2 + 127516^2 .

It is a cyclic number.

It is not a de Polignac number, because 42165554657 - 2²⁶ = 42098445793 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (42165551657) by changing a digit.

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 3 ways as a sum of consecutive naturals, for example, 3586358 + ... + 3598095.

It is an arithmetic number, because the mean of its divisors is an integer number (10543186245).

Almost surely, 2^42165554657 is an apocalyptic number.

It is an amenable number.

42165554657 is a deficient number, since it is larger than the sum of its proper divisors (7190323).

42165554657 is an equidigital number, since it uses as much as digits as its factorization.

42165554657 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7190322.

The product of its digits is 5040000, while the sum is 50.

The spelling of 42165554657 in words is "forty-two billion, one hundred sixty-five million, five hundred fifty-four thousand, six hundred fifty-seven".