21266856267278 has 16 divisors (see below), whose sum is σ = 33778220203440. Its totient is φ = 10007503180416.

The previous prime is 21266856267271. The next prime is 21266856267313. The reversal of 21266856267278 is 87276265866212.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21266856267271) 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, 12606701 + ... + 14193752.

It is an arithmetic number, because the mean of its divisors is an integer number (2111138762715).

Almost surely, 2^{21266856267278} is an apocalyptic number.

21266856267278 is a deficient number, since it is larger than the sum of its proper divisors (12511363936162).

21266856267278 is a wasteful number, since it uses less digits than its factorization.

21266856267278 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 26823811.

The product of its digits is 325140480, while the sum is 68.

The spelling of 21266856267278 in words is "twenty-one trillion, two hundred sixty-six billion, eight hundred fifty-six million, two hundred sixty-seven thousand, two hundred seventy-eight".