66553435566 has 64 divisors (see below), whose sum is σ = 156728174400. Its totient is φ = 20897049600.

The previous prime is 66553435523. The next prime is 66553435567.

66553435566 is a `hidden beast` number, since 6 + 6 + 55 + 34 + 3 + 556 + 6 = 666.

66553435566 is nontrivially palindromic in base 10.

It is a super-3 number, since 3×66553435566³ (a number of 33 digits) contains 333 as substring.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66553435567) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 454075 + ... + 582486.

It is an arithmetic number, because the mean of its divisors is an integer number (2448877725).

Almost surely, 2^66553435566 is an apocalyptic number.

66553435566 is an abundant number, since it is smaller than the sum of its proper divisors (90174738834).

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

66553435566 is a wasteful number, since it uses less digits than its factorization.

66553435566 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1036642 (or 1036636 counting only the distinct ones).

The product of its digits is 29160000, while the sum is 54.

The spelling of 66553435566 in words is "sixty-six billion, five hundred fifty-three million, four hundred thirty-five thousand, five hundred sixty-six".