66601566 has 12 divisors (see below), whose sum is σ = 144303432. Its totient is φ = 22200516.

The previous prime is 66601553. The next prime is 66601567. The reversal of 66601566 is 66510666.

It is a self number, because there is not a number n which added to its sum of digits gives 66601566.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66601567) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 1850026 + ... + 1850061.

It is an arithmetic number, because the mean of its divisors is an integer number (12025286).

Almost surely, 2^66601566 is an apocalyptic number.

66601566 is an abundant number, since it is smaller than the sum of its proper divisors (77701866).

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

66601566 is a wasteful number, since it uses less digits than its factorization.

66601566 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3700095 (or 3700092 counting only the distinct ones).

The product of its (nonzero) digits is 38880, while the sum is 36.

The square root of 66601566 is about 8160.9782501855. The cubic root of 66601566 is about 405.3481049184.

The spelling of 66601566 in words is "sixty-six million, six hundred one thousand, five hundred sixty-six".