1668267993 has 16 divisors (see below), whose sum is σ = 2652650496. Its totient is φ = 911848080.

The previous prime is 1668267973. The next prime is 1668268003. The reversal of 1668267993 is 3997628661.

It is a happy number.

It is not a de Polignac number, because 1668267993 - 2⁹ = 1668267481 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (1668267943) 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, 1726503 + ... + 1727468.

It is an arithmetic number, because the mean of its divisors is an integer number (165790656).

Almost surely, 2^1668267993 is an apocalyptic number.

It is an amenable number.

1668267993 is a deficient number, since it is larger than the sum of its proper divisors (984382503).

1668267993 is a wasteful number, since it uses less digits than its factorization.

1668267993 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3454004.

The product of its digits is 5878656, while the sum is 57.

The square root of 1668267993 is about 40844.4364999690. The cubic root of 1668267993 is about 1186.0106964125.

The spelling of 1668267993 in words is "one billion, six hundred sixty-eight million, two hundred sixty-seven thousand, nine hundred ninety-three".