42165554661 has 24 divisors (see below), whose sum is σ = 65162391840. Its totient is φ = 26194298400.

The previous prime is 42165554579. The next prime is 42165554723. The reversal of 42165554661 is 16645556124.

42165554661 is a `hidden beast` number, since 42 + 1 + 6 + 5 + 5 + 546 + 61 = 666.

42165554661 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 42165554661 - 2²³ = 42157166053 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (42165552661) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 2010735 + ... + 2031596.

It is an arithmetic number, because the mean of its divisors is an integer number (2715099660).

Almost surely, 2^42165554661 is an apocalyptic number.

It is an amenable number.

42165554661 is a deficient number, since it is larger than the sum of its proper divisors (22996837179).

42165554661 is a wasteful number, since it uses less digits than its factorization.

42165554661 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4042417 (or 4042414 counting only the distinct ones).

The product of its digits is 864000, while the sum is 45.

The spelling of 42165554661 in words is "forty-two billion, one hundred sixty-five million, five hundred fifty-four thousand, six hundred sixty-one".