21230011199989 has 2 divisors, whose sum is σ = 21230011199990. Its totient is φ = 21230011199988.

The previous prime is 21230011199987. The next prime is 21230011200017. The reversal of 21230011199989 is 98999111003212.

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., 15629490162225 + 5600521037764 = 3953415^2 + 2366542^2 .

It is a cyclic number.

It is not a de Polignac number, because 21230011199989 - 2¹ = 21230011199987 is a prime.

Together with 21230011199987, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21230011199987) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10615005599994 + 10615005599995.

It is an arithmetic number, because the mean of its divisors is an integer number (10615005599995).

Almost surely, 2^{21230011199989} is an apocalyptic number.

It is an amenable number.

21230011199989 is a deficient number, since it is larger than the sum of its proper divisors (1).

21230011199989 is an equidigital number, since it uses as much as digits as its factorization.

21230011199989 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 629856, while the sum is 55.

The spelling of 21230011199989 in words is "twenty-one trillion, two hundred thirty billion, eleven million, one hundred ninety-nine thousand, nine hundred eighty-nine".