1668821203 has 4 divisors (see below), whose sum is σ = 1907224240. Its totient is φ = 1430418168.

The previous prime is 1668821191. The next prime is 1668821213. The reversal of 1668821203 is 3021288661.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 1668821203 - 2²¹ = 1666724051 is a prime.

It is a super-3 number, since 3×1668821203³ (a number of 29 digits) contains 333 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1668821213) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 119201508 + ... + 119201521.

It is an arithmetic number, because the mean of its divisors is an integer number (476806060).

Almost surely, 2^1668821203 is an apocalyptic number.

1668821203 is a deficient number, since it is larger than the sum of its proper divisors (238403037).

1668821203 is an equidigital number, since it uses as much as digits as its factorization.

1668821203 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 238403036.

The product of its (nonzero) digits is 27648, while the sum is 37.

The square root of 1668821203 is about 40851.2080971910. The cubic root of 1668821203 is about 1186.1417785626.

The spelling of 1668821203 in words is "one billion, six hundred sixty-eight million, eight hundred twenty-one thousand, two hundred three".