1668838387 has 4 divisors (see below), whose sum is σ = 1670195296. Its totient is φ = 1667481480.

The previous prime is 1668838373. The next prime is 1668838399. The reversal of 1668838387 is 7838388661.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 7838388661 = 23 ⋅340799507.

It is a cyclic number.

It is not a de Polignac number, because 1668838387 - 2¹⁹ = 1668314099 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1668838307) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 676608 + ... + 679069.

It is an arithmetic number, because the mean of its divisors is an integer number (417548824).

Almost surely, 2^1668838387 is an apocalyptic number.

1668838387 is a deficient number, since it is larger than the sum of its proper divisors (1356909).

1668838387 is a wasteful number, since it uses less digits than its factorization.

1668838387 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1356908.

The product of its digits is 9289728, while the sum is 58.

The square root of 1668838387 is about 40851.4184209068. The cubic root of 1668838387 is about 1186.1458498177.

The spelling of 1668838387 in words is "one billion, six hundred sixty-eight million, eight hundred thirty-eight thousand, three hundred eighty-seven".