21311023412009 has 2 divisors, whose sum is σ = 21311023412010. Its totient is φ = 21311023412008.

The previous prime is 21311023411963. The next prime is 21311023412017. The reversal of 21311023412009 is 90021432011312.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 12020109802009 + 9290913610000 = 3467003^2 + 3048100^2 .

It is a cyclic number.

It is not a de Polignac number, because 21311023412009 - 2³² = 21306728444713 is a prime.

It is not a weakly prime, because it can be changed into another prime (21311023472009) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10655511706004 + 10655511706005.

It is an arithmetic number, because the mean of its divisors is an integer number (10655511706005).

Almost surely, 2^{21311023412009} is an apocalyptic number.

It is an amenable number.

21311023412009 is a deficient number, since it is larger than the sum of its proper divisors (1).

21311023412009 is an equidigital number, since it uses as much as digits as its factorization.

21311023412009 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 2592, while the sum is 29.

The spelling of 21311023412009 in words is "twenty-one trillion, three hundred eleven billion, twenty-three million, four hundred twelve thousand, nine".