666077999 has 4 divisors (see below), whose sum is σ = 695037936. Its totient is φ = 637118064.

The previous prime is 666077989. The next prime is 666078011. The reversal of 666077999 is 999770666.

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

It is a cyclic number.

It is not a de Polignac number, because 666077999 - 2⁴ = 666077983 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (666077939) 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, 14479934 + ... + 14479979.

It is an arithmetic number, because the mean of its divisors is an integer number (173759484).

Almost surely, 2^666077999 is an apocalyptic number.

666077999 is a deficient number, since it is larger than the sum of its proper divisors (28959937).

666077999 is a wasteful number, since it uses less digits than its factorization.

666077999 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 28959936.

The product of its (nonzero) digits is 7715736, while the sum is 59.

The square root of 666077999 is about 25808.4869568133. The cubic root of 666077999 is about 873.3232647319.

The spelling of 666077999 in words is "six hundred sixty-six million, seventy-seven thousand, nine hundred ninety-nine".