666828667 has 4 divisors (see below), whose sum is σ = 666952560. Its totient is φ = 666704776.

The previous prime is 666828653. The next prime is 666828683. The reversal of 666828667 is 766828666.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-666828667 is a prime.

It is a super-2 number, since 2×666828667² = 889320942265993778, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (666828607) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 53488 + ... + 64765.

It is an arithmetic number, because the mean of its divisors is an integer number (166738140).

Almost surely, 2^666828667 is an apocalyptic number.

666828667 is a deficient number, since it is larger than the sum of its proper divisors (123893).

666828667 is a wasteful number, since it uses less digits than its factorization.

666828667 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 123892.

The product of its digits is 6967296, while the sum is 55.

The square root of 666828667 is about 25823.0259071241. The cubic root of 666828667 is about 873.6512191687.

Subtracting 666828667 from its reverse (766828666), we obtain a palindrome (99999999).

The spelling of 666828667 in words is "six hundred sixty-six million, eight hundred twenty-eight thousand, six hundred sixty-seven".