21668850667 has 8 divisors (see below), whose sum is σ = 22199682960. Its totient is φ = 21142536480.

The previous prime is 21668850659. The next prime is 21668850677. The reversal of 21668850667 is 76605886612.

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

It is a cyclic number.

It is not a de Polignac number, because 21668850667 - 2³ = 21668850659 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21668850677) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1119817 + ... + 1139002.

It is an arithmetic number, because the mean of its divisors is an integer number (2774960370).

Almost surely, 2^21668850667 is an apocalyptic number.

21668850667 is a deficient number, since it is larger than the sum of its proper divisors (530832293).

21668850667 is a wasteful number, since it uses less digits than its factorization.

21668850667 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2259053.

The product of its (nonzero) digits is 5806080, while the sum is 55.

The spelling of 21668850667 in words is "twenty-one billion, six hundred sixty-eight million, eight hundred fifty thousand, six hundred sixty-seven".