28067911666 has 8 divisors (see below), whose sum is σ = 42574922460. Its totient is φ = 13876270848.

The previous prime is 28067911661. The next prime is 28067911681. The reversal of 28067911666 is 66611976082.

It can be written as a sum of positive squares in 2 ways, for example, as 25801675641 + 2266236025 = 160629^2 + 47605^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is not an unprimeable number, because it can be changed into a prime (28067911661) 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, 78842271 + ... + 78842626.

Almost surely, 2^28067911666 is an apocalyptic number.

28067911666 is a deficient number, since it is larger than the sum of its proper divisors (14507010794).

28067911666 is a wasteful number, since it uses less digits than its factorization.

28067911666 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 157684988.

The product of its (nonzero) digits is 1306368, while the sum is 52.

The spelling of 28067911666 in words is "twenty-eight billion, sixty-seven million, nine hundred eleven thousand, six hundred sixty-six".