667774166 has 4 divisors (see below), whose sum is σ = 1001661252. Its totient is φ = 333887082.

The previous prime is 667774139. The next prime is 667774181. The reversal of 667774166 is 661477766.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 661477766 = 2 ⋅330738883.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 166943540 + ... + 166943543.

It is an arithmetic number, because the mean of its divisors is an integer number (250415313).

Almost surely, 2^667774166 is an apocalyptic number.

667774166 is a deficient number, since it is larger than the sum of its proper divisors (333887086).

667774166 is a wasteful number, since it uses less digits than its factorization.

667774166 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 333887085.

The product of its digits is 1778112, while the sum is 50.

The square root of 667774166 is about 25841.3267074274. The cubic root of 667774166 is about 874.0639420008.

The spelling of 667774166 in words is "six hundred sixty-seven million, seven hundred seventy-four thousand, one hundred sixty-six".