21205337159089 has 2 divisors, whose sum is σ = 21205337159090. Its totient is φ = 21205337159088.

The previous prime is 21205337159087. The next prime is 21205337159093. The reversal of 21205337159089 is 98095173350212.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 19833065485489 + 1372271673600 = 4453433^2 + 1171440^2 .

It is a cyclic number.

It is not a de Polignac number, because 21205337159089 - 2¹ = 21205337159087 is a prime.

Together with 21205337159087, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (21205337159087) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10602668579544 + 10602668579545.

It is an arithmetic number, because the mean of its divisors is an integer number (10602668579545).

Almost surely, 2^{21205337159089} is an apocalyptic number.

It is an amenable number.

21205337159089 is a deficient number, since it is larger than the sum of its proper divisors (1).

21205337159089 is an equidigital number, since it uses as much as digits as its factorization.

21205337159089 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 4082400, while the sum is 55.

The spelling of 21205337159089 in words is "twenty-one trillion, two hundred five billion, three hundred thirty-seven million, one hundred fifty-nine thousand, eighty-nine".