2121668845 has 8 divisors (see below), whose sum is σ = 2547373176. Its totient is φ = 1696421376.

The previous prime is 2121668807. The next prime is 2121668869. The reversal of 2121668845 is 5488661212.

It can be written as a sum of positive squares in 4 ways, for example, as 91355364 + 2030313481 = 9558^2 + 45059^2 .

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

It is a cyclic number.

It is not a de Polignac number, because 2121668845 - 2²⁷ = 1987451117 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 103912 + ... + 122641.

It is an arithmetic number, because the mean of its divisors is an integer number (318421647).

Almost surely, 2^2121668845 is an apocalyptic number.

It is an amenable number.

2121668845 is a deficient number, since it is larger than the sum of its proper divisors (425704331).

2121668845 is a wasteful number, since it uses less digits than its factorization.

2121668845 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 228431.

The product of its digits is 184320, while the sum is 43.

The square root of 2121668845 is about 46061.5766664581. The cubic root of 2121668845 is about 1284.9686528107.

The spelling of 2121668845 in words is "two billion, one hundred twenty-one million, six hundred sixty-eight thousand, eight hundred forty-five".