66777688280 has 32 divisors (see below), whose sum is σ = 150821114400. Its totient is φ = 26609508096.

The previous prime is 66777688231. The next prime is 66777688283. The reversal of 66777688280 is 8288677766.

It is a super-3 number, since 3×66777688280³ (a number of 33 digits) contains 333 as substring.

It is a Smith number, since the sum of its digits (65) coincides with the sum of the digits of its prime factors.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66777688283) 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, 3163325 + ... + 3184364.

It is an arithmetic number, because the mean of its divisors is an integer number (4713159825).

Almost surely, 2^66777688280 is an apocalyptic number.

It is an amenable number.

66777688280 is an abundant number, since it is smaller than the sum of its proper divisors (84043426120).

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

66777688280 is a wasteful number, since it uses less digits than its factorization.

66777688280 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6347963 (or 6347959 counting only the distinct ones).

The product of its (nonzero) digits is 75866112, while the sum is 65.

The spelling of 66777688280 in words is "sixty-six billion, seven hundred seventy-seven million, six hundred eighty-eight thousand, two hundred eighty".