666206221473 has 16 divisors (see below), whose sum is σ = 1062893117440. Its totient is φ = 409973059152.

The previous prime is 666206221469. The next prime is 666206221481. The reversal of 666206221473 is 374122602666.

666206221473 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 666206221473 - 2² = 666206221469 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (666206221073) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 949011361 + ... + 949012062.

It is an arithmetic number, because the mean of its divisors is an integer number (66430819840).

Almost surely, 2^666206221473 is an apocalyptic number.

It is an amenable number.

666206221473 is a deficient number, since it is larger than the sum of its proper divisors (396686895967).

666206221473 is a wasteful number, since it uses less digits than its factorization.

666206221473 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1898023445 (or 1898023439 counting only the distinct ones).

The product of its (nonzero) digits is 870912, while the sum is 45.

The spelling of 666206221473 in words is "six hundred sixty-six billion, two hundred six million, two hundred twenty-one thousand, four hundred seventy-three".