21384938087 has 2 divisors, whose sum is σ = 21384938088. Its totient is φ = 21384938086.

The previous prime is 21384938051. The next prime is 21384938089. The reversal of 21384938087 is 78083948312.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21384938087 - 2¹² = 21384933991 is a prime.

Together with 21384938089, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21384938089) 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, 10692469043 + 10692469044.

It is an arithmetic number, because the mean of its divisors is an integer number (10692469044).

Almost surely, 2^21384938087 is an apocalyptic number.

21384938087 is a deficient number, since it is larger than the sum of its proper divisors (1).

21384938087 is an equidigital number, since it uses as much as digits as its factorization.

21384938087 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 2322432, while the sum is 53.

The spelling of 21384938087 in words is "twenty-one billion, three hundred eighty-four million, nine hundred thirty-eight thousand, eighty-seven".