2166072513661 has 8 divisors (see below), whose sum is σ = 2476451651904. Its totient is φ = 1855928427360.

The previous prime is 2166072513623. The next prime is 2166072513673. The reversal of 2166072513661 is 1663152706612.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 2166072513661 - 2⁹ = 2166072513149 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2166072513461) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 58743235 + ... + 58780096.

It is an arithmetic number, because the mean of its divisors is an integer number (309556456488).

Almost surely, 2^{2166072513661} is an apocalyptic number.

It is an amenable number.

2166072513661 is a deficient number, since it is larger than the sum of its proper divisors (310379138243).

2166072513661 is a wasteful number, since it uses less digits than its factorization.

2166072513661 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 117525971.

The product of its (nonzero) digits is 544320, while the sum is 46.

The spelling of 2166072513661 in words is "two trillion, one hundred sixty-six billion, seventy-two million, five hundred thirteen thousand, six hundred sixty-one".