21420388457099 has 2 divisors, whose sum is σ = 21420388457100. Its totient is φ = 21420388457098.

The previous prime is 21420388457051. The next prime is 21420388457137. The reversal of 21420388457099 is 99075488302412.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21420388457099 is a prime.

It is not a weakly prime, because it can be changed into another prime (21420388457029) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10710194228549 + 10710194228550.

It is an arithmetic number, because the mean of its divisors is an integer number (10710194228550).

Almost surely, 2^{21420388457099} is an apocalyptic number.

21420388457099 is a deficient number, since it is larger than the sum of its proper divisors (1).

21420388457099 is an equidigital number, since it uses as much as digits as its factorization.

21420388457099 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 34836480, while the sum is 62.

The spelling of 21420388457099 in words is "twenty-one trillion, four hundred twenty billion, three hundred eighty-eight million, four hundred fifty-seven thousand, ninety-nine".