21402123103247 has 2 divisors, whose sum is σ = 21402123103248. Its totient is φ = 21402123103246.

The previous prime is 21402123103181. The next prime is 21402123103271. The reversal of 21402123103247 is 74230132120412.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21402123103247 - 2³⁰ = 21401049361423 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21402123103447) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10701061551623 + 10701061551624.

It is an arithmetic number, because the mean of its divisors is an integer number (10701061551624).

Almost surely, 2^{21402123103247} is an apocalyptic number.

21402123103247 is a deficient number, since it is larger than the sum of its proper divisors (1).

21402123103247 is an equidigital number, since it uses as much as digits as its factorization.

21402123103247 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 16128, while the sum is 32.

Adding to 21402123103247 its reverse (74230132120412), we get a palindrome (95632255223659).

The spelling of 21402123103247 in words is "twenty-one trillion, four hundred two billion, one hundred twenty-three million, one hundred three thousand, two hundred forty-seven".