66877780 has 12 divisors (see below), whose sum is σ = 140443380. Its totient is φ = 26751104.

The previous prime is 66877753. The next prime is 66877793. The reversal of 66877780 is 8777866.

It can be written as a sum of positive squares in 2 ways, for example, as 26071236 + 40806544 = 5106^2 + 6388^2 .

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1671925 + ... + 1671964.

It is an arithmetic number, because the mean of its divisors is an integer number (11703615).

Almost surely, 2^66877780 is an apocalyptic number.

It is an amenable number.

66877780 is an abundant number, since it is smaller than the sum of its proper divisors (73565600).

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

66877780 is a wasteful number, since it uses less digits than its factorization.

66877780 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3343898 (or 3343896 counting only the distinct ones).

The product of its (nonzero) digits is 790272, while the sum is 49.

The square root of 66877780 is about 8177.8835892913. The cubic root of 66877780 is about 405.9076933493.

It can be divided in two parts, 6 and 6877780, that added together give a palindrome (6877786).

The spelling of 66877780 in words is "sixty-six million, eight hundred seventy-seven thousand, seven hundred eighty".