21900856267 has 2 divisors, whose sum is σ = 21900856268. Its totient is φ = 21900856266.

The previous prime is 21900856253. The next prime is 21900856273. The reversal of 21900856267 is 76265800912.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21900856267 - 2⁷ = 21900856139 is a prime.

It is not a weakly prime, because it can be changed into another prime (21900856297) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10950428133 + 10950428134.

It is an arithmetic number, because the mean of its divisors is an integer number (10950428134).

Almost surely, 2^21900856267 is an apocalyptic number.

21900856267 is a deficient number, since it is larger than the sum of its proper divisors (1).

21900856267 is an equidigital number, since it uses as much as digits as its factorization.

21900856267 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 362880, while the sum is 46.

The spelling of 21900856267 in words is "twenty-one billion, nine hundred million, eight hundred fifty-six thousand, two hundred sixty-seven".