66622878 has 64 divisors (see below), whose sum is σ = 170027520. Its totient is φ = 18942336.

The previous prime is 66622877. The next prime is 66622883. The reversal of 66622878 is 87822666.

It is a happy number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66622877) 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, 127125 + ... + 127647.

It is an arithmetic number, because the mean of its divisors is an integer number (2656680).

Almost surely, 2^66622878 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 66622878, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (85013760).

66622878 is an abundant number, since it is smaller than the sum of its proper divisors (103404642).

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

66622878 is a wasteful number, since it uses less digits than its factorization.

66622878 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 878 (or 872 counting only the distinct ones).

The product of its digits is 387072, while the sum is 45.

The square root of 66622878 is about 8162.2838715644. The cubic root of 66622878 is about 405.3913364220.

The spelling of 66622878 in words is "sixty-six million, six hundred twenty-two thousand, eight hundred seventy-eight".