66863778 has 8 divisors (see below), whose sum is σ = 133727568. Its totient is φ = 22287924.

The previous prime is 66863711. The next prime is 66863779. The reversal of 66863778 is 87736866.

66863778 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a sphenic number, since it is the product of 3 distinct primes.

66863778 is an admirable number.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 66863778.

It is not an unprimeable number, because it can be changed into a prime (66863779) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5571976 + ... + 5571987.

It is an arithmetic number, because the mean of its divisors is an integer number (16715946).

Almost surely, 2^66863778 is an apocalyptic number.

66863778 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

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

66863778 is a wasteful number, since it uses less digits than its factorization.

66863778 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11143968.

The product of its digits is 2032128, while the sum is 51.

The square root of 66863778 is about 8177.0274550108. The cubic root of 66863778 is about 405.8793634805.

It can be divided in two parts, 668 and 63778, that added together give a palindrome (64446).

The spelling of 66863778 in words is "sixty-six million, eight hundred sixty-three thousand, seven hundred seventy-eight".