21251303042239 has 2 divisors, whose sum is σ = 21251303042240. Its totient is φ = 21251303042238.

The previous prime is 21251303042149. The next prime is 21251303042261. The reversal of 21251303042239 is 93224030315212.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21251303042239 - 2²¹ = 21251300945087 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21251303042198 and 21251303042207.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21251300042239) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10625651521119 + 10625651521120.

It is an arithmetic number, because the mean of its divisors is an integer number (10625651521120).

Almost surely, 2^{21251303042239} is an apocalyptic number.

21251303042239 is a deficient number, since it is larger than the sum of its proper divisors (1).

21251303042239 is an equidigital number, since it uses as much as digits as its factorization.

21251303042239 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 77760, while the sum is 37.

The spelling of 21251303042239 in words is "twenty-one trillion, two hundred fifty-one billion, three hundred three million, forty-two thousand, two hundred thirty-nine".