66868894278 has 16 divisors (see below), whose sum is σ = 148597542960. Its totient is φ = 22289631408.

The previous prime is 66868894277. The next prime is 66868894283. The reversal of 66868894278 is 87249886866.

66868894278 is a `hidden beast` number, since 6 + 68 + 68 + 89 + 427 + 8 = 666.

66868894278 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a super-2 number, since 2×66868894278² (a number of 22 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66868894271) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 619156375 + ... + 619156482.

It is an arithmetic number, because the mean of its divisors is an integer number (9287346435).

Almost surely, 2^66868894278 is an apocalyptic number.

66868894278 is an abundant number, since it is smaller than the sum of its proper divisors (81728648682).

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

66868894278 is a wasteful number, since it uses less digits than its factorization.

66868894278 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1238312868 (or 1238312862 counting only the distinct ones).

The product of its digits is 445906944, while the sum is 72.

The spelling of 66868894278 in words is "sixty-six billion, eight hundred sixty-eight million, eight hundred ninety-four thousand, two hundred seventy-eight".