21550698353 has 2 divisors, whose sum is σ = 21550698354. Its totient is φ = 21550698352.

The previous prime is 21550698311. The next prime is 21550698391. The reversal of 21550698353 is 35389605512.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 15071736289 + 6478962064 = 122767^2 + 80492^2 .

It is a cyclic number.

It is not a de Polignac number, because 21550698353 - 2⁸ = 21550698097 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21550698298 and 21550698307.

It is not a weakly prime, because it can be changed into another prime (21550698853) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10775349176 + 10775349177.

It is an arithmetic number, because the mean of its divisors is an integer number (10775349177).

Almost surely, 2^21550698353 is an apocalyptic number.

It is an amenable number.

21550698353 is a deficient number, since it is larger than the sum of its proper divisors (1).

21550698353 is an equidigital number, since it uses as much as digits as its factorization.

21550698353 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 972000, while the sum is 47.

The spelling of 21550698353 in words is "twenty-one billion, five hundred fifty million, six hundred ninety-eight thousand, three hundred fifty-three".