19095871666 has 4 divisors (see below), whose sum is σ = 28643807502. Its totient is φ = 9547935832.

The previous prime is 19095871649. The next prime is 19095871727. The reversal of 19095871666 is 66617859091.

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

It can be written as a sum of positive squares in only one way, i.e., 16325428441 + 2770443225 = 127771^2 + 52635^2 .

It is a Smith number, since the sum of its digits (58) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a self number, because there is not a number n which added to its sum of digits gives 19095871666.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4773967915 + ... + 4773967918.

Almost surely, 2^19095871666 is an apocalyptic number.

19095871666 is a deficient number, since it is larger than the sum of its proper divisors (9547935836).

19095871666 is an equidigital number, since it uses as much as digits as its factorization.

19095871666 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9547935835.

The product of its (nonzero) digits is 4898880, while the sum is 58.

The spelling of 19095871666 in words is "nineteen billion, ninety-five million, eight hundred seventy-one thousand, six hundred sixty-six".