166775577661 has 8 divisors (see below), whose sum is σ = 207927993024. Its totient is φ = 129954995520.

The previous prime is 166775577653. The next prime is 166775577673.

It is a happy number.

166775577661 is nontrivially palindromic in base 10.

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

It is not a de Polignac number, because 166775577661 - 2³ = 166775577653 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 166775577593 and 166775577602.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (166775577061) 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, 1082958220 + ... + 1082958373.

It is an arithmetic number, because the mean of its divisors is an integer number (25990999128).

Almost surely, 2^166775577661 is an apocalyptic number.

166775577661 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

166775577661 is a deficient number, since it is larger than the sum of its proper divisors (41152415363).

166775577661 is a wasteful number, since it uses less digits than its factorization.

166775577661 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2165916611.

The product of its digits is 77792400, while the sum is 64.

The spelling of 166775577661 in words is "one hundred sixty-six billion, seven hundred seventy-five million, five hundred seventy-seven thousand, six hundred sixty-one".