6661721914 has 8 divisors (see below), whose sum is σ = 10011690720. Its totient is φ = 3324491676.

The previous prime is 6661721903. The next prime is 6661721939. The reversal of 6661721914 is 4191271666.

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

It is an unprimeable number.

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, 3183334 + ... + 3185425.

It is an arithmetic number, because the mean of its divisors is an integer number (1251461340).

Almost surely, 2^6661721914 is an apocalyptic number.

6661721914 is a deficient number, since it is larger than the sum of its proper divisors (3349968806).

6661721914 is a wasteful number, since it uses less digits than its factorization.

6661721914 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6369284.

The product of its digits is 108864, while the sum is 43.

The square root of 6661721914 is about 81619.3721735226. The cubic root of 6661721914 is about 1881.6066236289.

The spelling of 6661721914 in words is "six billion, six hundred sixty-one million, seven hundred twenty-one thousand, nine hundred fourteen".