16668335000021 has 4 divisors (see below), whose sum is σ = 16674768169344. Its totient is φ = 16661901830700.

The previous prime is 16668334999997. The next prime is 16668335000027. The reversal of 16668335000021 is 12000053386661.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 16668335000021 - 2¹⁴ = 16668334983637 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 (16668335000027) 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, 3216580775 + ... + 3216585956.

It is an arithmetic number, because the mean of its divisors is an integer number (4168692042336).

Almost surely, 2^{16668335000021} is an apocalyptic number.

It is an amenable number.

16668335000021 is a deficient number, since it is larger than the sum of its proper divisors (6433169323).

16668335000021 is an equidigital number, since it uses as much as digits as its factorization.

16668335000021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6433169322.

The product of its (nonzero) digits is 155520, while the sum is 41.

Adding to 16668335000021 its reverse (12000053386661), we get a palindrome (28668388386682).

The spelling of 16668335000021 in words is "sixteen trillion, six hundred sixty-eight billion, three hundred thirty-five million, twenty-one", and thus it is an aban number.