66868270921 has 9 divisors (see below), whose sum is σ = 69908210029. Its totient is φ = 63955265836.

The previous prime is 66868270919. The next prime is 66868270961. The reversal of 66868270921 is 12907286866.

The square root of 66868270921 is 258589.

It is a perfect power (a square), and thus also a powerful number.

It is not a de Polignac number, because 66868270921 - 2¹ = 66868270919 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (66868270961) by changing a digit.

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 8 ways as a sum of consecutive naturals, for example, 5941926 + ... + 5953168.

Almost surely, 2^66868270921 is an apocalyptic number.

66868270921 is the 258589-th square number.

66868270921 is the 129295-th centered octagonal number.

It is an amenable number.

66868270921 is a deficient number, since it is larger than the sum of its proper divisors (3039939108).

66868270921 is an frugal number, since it uses more digits than its factorization.

66868270921 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 22532 (or 11266 counting only the distinct ones).

The product of its (nonzero) digits is 3483648, while the sum is 55.

The spelling of 66868270921 in words is "sixty-six billion, eight hundred sixty-eight million, two hundred seventy thousand, nine hundred twenty-one".