2666455661 has 8 divisors (see below), whose sum is σ = 2830424760. Its totient is φ = 2503277568.

The previous prime is 2666455643. The next prime is 2666455667. The reversal of 2666455661 is 1665546662.

It can be written as a sum of positive squares in 4 ways, for example, as 1446280900 + 1220174761 = 38030^2 + 34931^2 .

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

It is a cyclic number.

It is not a de Polignac number, because 2666455661 - 2¹⁴ = 2666439277 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2666455667) 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, 190796 + ... + 204293.

It is an arithmetic number, because the mean of its divisors is an integer number (353803095).

Almost surely, 2^2666455661 is an apocalyptic number.

It is an amenable number.

2666455661 is a deficient number, since it is larger than the sum of its proper divisors (163969099).

2666455661 is a wasteful number, since it uses less digits than its factorization.

2666455661 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 395503.

The product of its digits is 1555200, while the sum is 47.

The square root of 2666455661 is about 51637.7348554330. The cubic root of 2666455661 is about 1386.6859719470.

The spelling of 2666455661 in words is "two billion, six hundred sixty-six million, four hundred fifty-five thousand, six hundred sixty-one".