21212021459 has 2 divisors, whose sum is σ = 21212021460. Its totient is φ = 21212021458.

The previous prime is 21212021431. The next prime is 21212021461. The reversal of 21212021459 is 95412021212.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21212021459 - 2²⁸ = 20943586003 is a prime.

It is a Sophie Germain prime.

Together with 21212021461, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (21212021659) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10606010729 + 10606010730.

It is an arithmetic number, because the mean of its divisors is an integer number (10606010730).

Almost surely, 2^21212021459 is an apocalyptic number.

21212021459 is a deficient number, since it is larger than the sum of its proper divisors (1).

21212021459 is an equidigital number, since it uses as much as digits as its factorization.

21212021459 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 2880, while the sum is 29.

The spelling of 21212021459 in words is "twenty-one billion, two hundred twelve million, twenty-one thousand, four hundred fifty-nine".