21056541166266 has 8 divisors (see below), whose sum is σ = 42113082332544. Its totient is φ = 7018847055420.

The previous prime is 21056541166261. The next prime is 21056541166277. The reversal of 21056541166266 is 66266114565012.

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

21056541166266 is an admirable number.

It is not an unprimeable number, because it can be changed into a prime (21056541166261) 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, 1754711763850 + ... + 1754711763861.

It is an arithmetic number, because the mean of its divisors is an integer number (5264135291568).

Almost surely, 2^{21056541166266} is an apocalyptic number.

21056541166266 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21056541166266 is a wasteful number, since it uses less digits than its factorization.

21056541166266 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3509423527716.

The product of its (nonzero) digits is 3110400, while the sum is 51.

The spelling of 21056541166266 in words is "twenty-one trillion, fifty-six billion, five hundred forty-one million, one hundred sixty-six thousand, two hundred sixty-six".