6661746553 has 16 divisors (see below), whose sum is σ = 8386200576. Its totient is φ = 5140567440.

The previous prime is 6661746547. The next prime is 6661746557. The reversal of 6661746553 is 3556471666.

It is a cyclic number.

It is not a de Polignac number, because 6661746553 - 2⁵ = 6661746521 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 6661746497 and 6661746506.

It is not an unprimeable number, because it can be changed into a prime (6661746557) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 412051 + ... + 427912.

It is an arithmetic number, because the mean of its divisors is an integer number (524137536).

Almost surely, 2^6661746553 is an apocalyptic number.

It is an amenable number.

6661746553 is a deficient number, since it is larger than the sum of its proper divisors (1724454023).

6661746553 is a wasteful number, since it uses less digits than its factorization.

6661746553 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 840084.

The product of its digits is 2721600, while the sum is 49.

The square root of 6661746553 is about 81619.5231118144. The cubic root of 6661746553 is about 1881.6089433919.

The spelling of 6661746553 in words is "six billion, six hundred sixty-one million, seven hundred forty-six thousand, five hundred fifty-three".