66694878 has 12 divisors (see below), whose sum is σ = 144505608. Its totient is φ = 22231620.

The previous prime is 66694877. The next prime is 66694891. The reversal of 66694878 is 87849666.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66694877) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 1852618 + ... + 1852653.

It is an arithmetic number, because the mean of its divisors is an integer number (12042134).

Almost surely, 2^66694878 is an apocalyptic number.

66694878 is an abundant number, since it is smaller than the sum of its proper divisors (77810730).

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

66694878 is a wasteful number, since it uses less digits than its factorization.

66694878 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3705279 (or 3705276 counting only the distinct ones).

The product of its digits is 3483648, while the sum is 54.

The square root of 66694878 is about 8166.6932108412. The cubic root of 66694878 is about 405.5373206483.

The spelling of 66694878 in words is "sixty-six million, six hundred ninety-four thousand, eight hundred seventy-eight".