6653565666 has 60 divisors (see below), whose sum is σ = 16387534086. Its totient is φ = 2016226080.

The previous prime is 6653565661. The next prime is 6653565679. The reversal of 6653565666 is 6665653566.

It can be written as a sum of positive squares in only one way, i.e., 6510069225 + 143496441 = 80685^2 + 11979^2 .

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (6653565661) by changing a digit.

It is a polite number, since it can be written in 29 ways as a sum of consecutive naturals, for example, 150115 + ... + 189318.

Almost surely, 2^6653565666 is an apocalyptic number.

6653565666 is a gapful number since it is divisible by the number (66) formed by its first and last digit.

6653565666 is an abundant number, since it is smaller than the sum of its proper divisors (9733968420).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

6653565666 is a wasteful number, since it uses less digits than its factorization.

6653565666 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 339469 (or 339449 counting only the distinct ones).

The product of its digits is 17496000, while the sum is 54.

The square root of 6653565666 is about 81569.3917226309. The cubic root of 6653565666 is about 1880.8383979357.

The spelling of 6653565666 in words is "six billion, six hundred fifty-three million, five hundred sixty-five thousand, six hundred sixty-six".