21304440539 has 2 divisors, whose sum is σ = 21304440540. Its totient is φ = 21304440538.

The previous prime is 21304440473. The next prime is 21304440611. The reversal of 21304440539 is 93504440312.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21304440539 - 2¹² = 21304436443 is a prime.

It is a super-2 number, since 2×21304440539² (a number of 21 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 21304440499 and 21304440508.

It is not a weakly prime, because it can be changed into another prime (21304440139) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10652220269 + 10652220270.

It is an arithmetic number, because the mean of its divisors is an integer number (10652220270).

Almost surely, 2^21304440539 is an apocalyptic number.

21304440539 is a deficient number, since it is larger than the sum of its proper divisors (1).

21304440539 is an equidigital number, since it uses as much as digits as its factorization.

21304440539 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 51840, while the sum is 35.

The spelling of 21304440539 in words is "twenty-one billion, three hundred four million, four hundred forty thousand, five hundred thirty-nine".