21550698853 has 2 divisors, whose sum is σ = 21550698854. Its totient is φ = 21550698852.

The previous prime is 21550698847. The next prime is 21550698893. The reversal of 21550698853 is 35889605512.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 21369177124 + 181521729 = 146182^2 + 13473^2 .

It is a cyclic number.

It is not a de Polignac number, because 21550698853 - 2⁵ = 21550698821 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21550698853.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21550698893) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10775349426 + 10775349427.

It is an arithmetic number, because the mean of its divisors is an integer number (10775349427).

Almost surely, 2^21550698853 is an apocalyptic number.

It is an amenable number.

21550698853 is a deficient number, since it is larger than the sum of its proper divisors (1).

21550698853 is an equidigital number, since it uses as much as digits as its factorization.

21550698853 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 2592000, while the sum is 52.

The spelling of 21550698853 in words is "twenty-one billion, five hundred fifty million, six hundred ninety-eight thousand, eight hundred fifty-three".