21266655061321 has 8 divisors (see below), whose sum is σ = 22018904614080. Its totient is φ = 20515666616592.

The previous prime is 21266655061319. The next prime is 21266655061343. The reversal of 21266655061321 is 12316055666212.

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 21266655061321 - 2¹ = 21266655061319 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21266655061121) 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, 315242685 + ... + 315310138.

It is an arithmetic number, because the mean of its divisors is an integer number (2752363076760).

Almost surely, 2^{21266655061321} is an apocalyptic number.

It is an amenable number.

21266655061321 is a deficient number, since it is larger than the sum of its proper divisors (752249552759).

21266655061321 is a wasteful number, since it uses less digits than its factorization.

21266655061321 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 630554015.

The product of its (nonzero) digits is 777600, while the sum is 46.

The spelling of 21266655061321 in words is "twenty-one trillion, two hundred sixty-six billion, six hundred fifty-five million, sixty-one thousand, three hundred twenty-one".