21304134539 has 2 divisors, whose sum is σ = 21304134540. Its totient is φ = 21304134538.

The previous prime is 21304134499. The next prime is 21304134569. The reversal of 21304134539 is 93543140312.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21304134539 - 2²⁴ = 21287357323 is a prime.

It is a super-2 number, since 2×21304134539² (a number of 21 digits) contains 22 as substring.

It is a Sophie Germain prime.

It is a junction number, because it is equal to n+sod(n) for n = 21304134499 and 21304134508.

It is not a weakly prime, because it can be changed into another prime (21304134569) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10652067269 + 10652067270.

It is an arithmetic number, because the mean of its divisors is an integer number (10652067270).

Almost surely, 2^21304134539 is an apocalyptic number.

21304134539 is a deficient number, since it is larger than the sum of its proper divisors (1).

21304134539 is an equidigital number, since it uses as much as digits as its factorization.

21304134539 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 38880, while the sum is 35.

The spelling of 21304134539 in words is "twenty-one billion, three hundred four million, one hundred thirty-four thousand, five hundred thirty-nine".