21255446089 has 2 divisors, whose sum is σ = 21255446090. Its totient is φ = 21255446088.

The previous prime is 21255446077. The next prime is 21255446123. The reversal of 21255446089 is 98064455212.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 15327678025 + 5927768064 = 123805^2 + 76992^2 .

It is a cyclic number.

It is not a de Polignac number, because 21255446089 - 2⁷ = 21255445961 is a prime.

It is not a weakly prime, because it can be changed into another prime (21255446039) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10627723044 + 10627723045.

It is an arithmetic number, because the mean of its divisors is an integer number (10627723045).

Almost surely, 2^21255446089 is an apocalyptic number.

It is an amenable number.

21255446089 is a deficient number, since it is larger than the sum of its proper divisors (1).

21255446089 is an equidigital number, since it uses as much as digits as its factorization.

21255446089 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 691200, while the sum is 46.

The spelling of 21255446089 in words is "twenty-one billion, two hundred fifty-five million, four hundred forty-six thousand, eighty-nine".