1668328221172 has 12 divisors (see below), whose sum is σ = 2919703110660. Its totient is φ = 834127332416.

The previous prime is 1668328221169. The next prime is 1668328221181. The reversal of 1668328221172 is 2711228238661.

It can be written as a sum of positive squares in 2 ways, for example, as 216221280016 + 1452106941156 = 464996^2 + 1205034^2 .

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 9092353 + ... + 9274024.

It is an arithmetic number, because the mean of its divisors is an integer number (243308592555).

Almost surely, 2^{1668328221172} is an apocalyptic number.

It is an amenable number.

1668328221172 is a deficient number, since it is larger than the sum of its proper divisors (1251374889488).

1668328221172 is a wasteful number, since it uses less digits than its factorization.

1668328221172 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18389090 (or 18389088 counting only the distinct ones).

The product of its digits is 774144, while the sum is 49.

The spelling of 1668328221172 in words is "one trillion, six hundred sixty-eight billion, three hundred twenty-eight million, two hundred twenty-one thousand, one hundred seventy-two".