21030402193 has 2 divisors, whose sum is σ = 21030402194. Its totient is φ = 21030402192.

The previous prime is 21030402191. The next prime is 21030402229. The reversal of 21030402193 is 39120403012.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 19178649169 + 1851753024 = 138487^2 + 43032^2 .

It is a cyclic number.

It is not a de Polignac number, because 21030402193 - 2¹ = 21030402191 is a prime.

Together with 21030402191, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (21030402191) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10515201096 + 10515201097.

It is an arithmetic number, because the mean of its divisors is an integer number (10515201097).

Almost surely, 2^21030402193 is an apocalyptic number.

It is an amenable number.

21030402193 is a deficient number, since it is larger than the sum of its proper divisors (1).

21030402193 is an equidigital number, since it uses as much as digits as its factorization.

21030402193 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1296, while the sum is 25.

The spelling of 21030402193 in words is "twenty-one billion, thirty million, four hundred two thousand, one hundred ninety-three".