1668686703638 has 8 divisors (see below), whose sum is σ = 2503208923632. Its totient is φ = 834283729096.

The previous prime is 1668686703637. The next prime is 1668686703667. The reversal of 1668686703638 is 8363076868661.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1668686703637) 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, 29776370 + ... + 29832357.

It is an arithmetic number, because the mean of its divisors is an integer number (312901115454).

Almost surely, 2^{1668686703638} is an apocalyptic number.

1668686703638 is a deficient number, since it is larger than the sum of its proper divisors (834522219994).

1668686703638 is a wasteful number, since it uses less digits than its factorization.

1668686703638 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 59622726.

The product of its (nonzero) digits is 250822656, while the sum is 68.

The spelling of 1668686703638 in words is "one trillion, six hundred sixty-eight billion, six hundred eighty-six million, seven hundred three thousand, six hundred thirty-eight".