667578875766 has 64 divisors (see below), whose sum is σ = 1504859973120. Its totient is φ = 195650415360.

The previous prime is 667578875759. The next prime is 667578875771.

667578875766 is nontrivially palindromic in base 10.

It is a junction number, because it is equal to n+sod(n) for n = 667578875691 and 667578875700.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 410671 + ... + 1226298.

It is an arithmetic number, because the mean of its divisors is an integer number (23513437080).

Almost surely, 2^667578875766 is an apocalyptic number.

667578875766 is a gapful number since it is divisible by the number (66) formed by its first and last digit.

667578875766 is an abundant number, since it is smaller than the sum of its proper divisors (837281097354).

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

667578875766 is a wasteful number, since it uses less digits than its factorization.

667578875766 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1637189.

The product of its digits is 4978713600, while the sum is 78.

The spelling of 667578875766 in words is "six hundred sixty-seven billion, five hundred seventy-eight million, eight hundred seventy-five thousand, seven hundred sixty-six".