1668211047 has 6 divisors (see below), whose sum is σ = 2409638192. Its totient is φ = 1112140692.

The previous prime is 1668211033. The next prime is 1668211049. The reversal of 1668211047 is 7401128661.

It is a happy number.

It is not a de Polignac number, because 1668211047 - 2⁴ = 1668211031 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1668211049) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 92678383 + ... + 92678400.

Almost surely, 2^1668211047 is an apocalyptic number.

1668211047 is a deficient number, since it is larger than the sum of its proper divisors (741427145).

1668211047 is a wasteful number, since it uses less digits than its factorization.

1668211047 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 185356789 (or 185356786 counting only the distinct ones).

The product of its (nonzero) digits is 16128, while the sum is 36.

The square root of 1668211047 is about 40843.7393856145. The cubic root of 1668211047 is about 1185.9972015116.

The spelling of 1668211047 in words is "one billion, six hundred sixty-eight million, two hundred eleven thousand, forty-seven".