21233010209 has 2 divisors, whose sum is σ = 21233010210. Its totient is φ = 21233010208.

The previous prime is 21233010193. The next prime is 21233010223. The reversal of 21233010209 is 90201033212.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 21185675809 + 47334400 = 145553^2 + 6880^2 .

It is a cyclic number.

It is not a de Polignac number, because 21233010209 - 2⁴ = 21233010193 is a prime.

It is not a weakly prime, because it can be changed into another prime (21233010229) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10616505104 + 10616505105.

It is an arithmetic number, because the mean of its divisors is an integer number (10616505105).

Almost surely, 2^21233010209 is an apocalyptic number.

It is an amenable number.

21233010209 is a deficient number, since it is larger than the sum of its proper divisors (1).

21233010209 is an equidigital number, since it uses as much as digits as its factorization.

21233010209 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 648, while the sum is 23.

The spelling of 21233010209 in words is "twenty-one billion, two hundred thirty-three million, ten thousand, two hundred nine".