21021211499 has 2 divisors, whose sum is σ = 21021211500. Its totient is φ = 21021211498.

The previous prime is 21021211451. The next prime is 21021211513. The reversal of 21021211499 is 99411212012.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21021211499 - 2³² = 16726244203 is a prime.

It is a Sophie Germain prime.

It is not a weakly prime, because it can be changed into another prime (21021211439) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10510605749 + 10510605750.

It is an arithmetic number, because the mean of its divisors is an integer number (10510605750).

Almost surely, 2^21021211499 is an apocalyptic number.

21021211499 is a deficient number, since it is larger than the sum of its proper divisors (1).

21021211499 is an equidigital number, since it uses as much as digits as its factorization.

21021211499 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 32.

The spelling of 21021211499 in words is "twenty-one billion, twenty-one million, two hundred eleven thousand, four hundred ninety-nine".