2196658891 has 4 divisors (see below), whose sum is σ = 2510467312. Its totient is φ = 1882850472.

The previous prime is 2196658889. The next prime is 2196658901. The reversal of 2196658891 is 1988566912.

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 2196658891 - 2¹ = 2196658889 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (2196655891) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 156904200 + ... + 156904213.

It is an arithmetic number, because the mean of its divisors is an integer number (627616828).

Almost surely, 2^2196658891 is an apocalyptic number.

2196658891 is a deficient number, since it is larger than the sum of its proper divisors (313808421).

2196658891 is an equidigital number, since it uses as much as digits as its factorization.

2196658891 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 313808420.

The product of its digits is 1866240, while the sum is 55.

The square root of 2196658891 is about 46868.5277238362. The cubic root of 2196658891 is about 1299.9327166361.

The spelling of 2196658891 in words is "two billion, one hundred ninety-six million, six hundred fifty-eight thousand, eight hundred ninety-one".