66217875 has 32 divisors (see below), whose sum is σ = 114004800. Its totient is φ = 34092800.

The previous prime is 66217867. The next prime is 66217889. The reversal of 66217875 is 57871266.

It is not a de Polignac number, because 66217875 - 2³ = 66217867 is a prime.

It is a hoax number, since the sum of its digits (42) coincides with the sum of the digits of its distinct prime factors.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 7831 + ... + 13919.

It is an arithmetic number, because the mean of its divisors is an integer number (3562650).

Almost surely, 2^66217875 is an apocalyptic number.

66217875 is the 4350-th nonagonal number.

66217875 is a deficient number, since it is larger than the sum of its proper divisors (47786925).

66217875 is a wasteful number, since it uses less digits than its factorization.

66217875 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6136 (or 6126 counting only the distinct ones).

The product of its digits is 141120, while the sum is 42.

The square root of 66217875 is about 8137.4366356980. The cubic root of 66217875 is about 404.5682031103.

The spelling of 66217875 in words is "sixty-six million, two hundred seventeen thousand, eight hundred seventy-five".