2191960066 has 4 divisors (see below), whose sum is σ = 3287940102. Its totient is φ = 1095980032.

The previous prime is 2191960037. The next prime is 2191960109. The reversal of 2191960066 is 6600691912.

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., 1275989841 + 915970225 = 35721^2 + 30265^2 .

It is a Smith number, since the sum of its digits (40) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 547990015 + ... + 547990018.

Almost surely, 2^2191960066 is an apocalyptic number.

2191960066 is a deficient number, since it is larger than the sum of its proper divisors (1095980036).

2191960066 is a wasteful number, since it uses less digits than its factorization.

2191960066 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1095980035.

The product of its (nonzero) digits is 34992, while the sum is 40.

The square root of 2191960066 is about 46818.3731669523. The cubic root of 2191960066 is about 1299.0051690728.

The spelling of 2191960066 in words is "two billion, one hundred ninety-one million, nine hundred sixty thousand, sixty-six".