6661615066 has 8 divisors (see below), whose sum is σ = 10000556820. Its totient is φ = 3328096128.

The previous prime is 6661615063. The next prime is 6661615069. The reversal of 6661615066 is 6605161666.

It is an interprime number because it is at equal distance from previous prime (6661615063) and next prime (6661615069).

It can be written as a sum of positive squares in 2 ways, for example, as 6661008225 + 606841 = 81615^2 + 779^2 .

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

It is not an unprimeable number, because it can be changed into a prime (6661615063) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1352631 + ... + 1357546.

Almost surely, 2^6661615066 is an apocalyptic number.

6661615066 is a deficient number, since it is larger than the sum of its proper divisors (3338941754).

6661615066 is a wasteful number, since it uses less digits than its factorization.

6661615066 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2711408.

The product of its (nonzero) digits is 233280, while the sum is 43.

The square root of 6661615066 is about 81618.7176204086. The cubic root of 6661615066 is about 1881.5965638185.

The spelling of 6661615066 in words is "six billion, six hundred sixty-one million, six hundred fifteen thousand, sixty-six".