21212002193 has 2 divisors, whose sum is σ = 21212002194. Its totient is φ = 21212002192.

The previous prime is 21212002169. The next prime is 21212002261. The reversal of 21212002193 is 39120021212.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 16296309649 + 4915692544 = 127657^2 + 70112^2 .

It is a cyclic number.

It is not a de Polignac number, because 21212002193 - 2¹⁰ = 21212001169 is a prime.

It is not a weakly prime, because it can be changed into another prime (21212022193) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10606001096 + 10606001097.

It is an arithmetic number, because the mean of its divisors is an integer number (10606001097).

Almost surely, 2^21212002193 is an apocalyptic number.

It is an amenable number.

21212002193 is a deficient number, since it is larger than the sum of its proper divisors (1).

21212002193 is an equidigital number, since it uses as much as digits as its factorization.

21212002193 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 432, while the sum is 23.

The spelling of 21212002193 in words is "twenty-one billion, two hundred twelve million, two thousand, one hundred ninety-three".