21454304666 has 8 divisors (see below), whose sum is σ = 32228994420. Its totient is φ = 10711306528.

The previous prime is 21454304593. The next prime is 21454304737. The reversal of 21454304666 is 66640345412.

It can be written as a sum of positive squares in 2 ways, for example, as 13422381025 + 8031923641 = 115855^2 + 89621^2 .

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

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 7921211 + ... + 7923918.

Almost surely, 2^21454304666 is an apocalyptic number.

21454304666 is a deficient number, since it is larger than the sum of its proper divisors (10774689754).

21454304666 is a wasteful number, since it uses less digits than its factorization.

21454304666 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15845808.

The product of its (nonzero) digits is 414720, while the sum is 41.

The spelling of 21454304666 in words is "twenty-one billion, four hundred fifty-four million, three hundred four thousand, six hundred sixty-six".