21043030039 has 2 divisors, whose sum is σ = 21043030040. Its totient is φ = 21043030038.

The previous prime is 21043030003. The next prime is 21043030097. The reversal of 21043030039 is 93003034012.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21043030039 - 2¹⁵ = 21042997271 is a prime.

It is a super-2 number, since 2×21043030039² (a number of 21 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 21043029995 and 21043030022.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21043090039) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10521515019 + 10521515020.

It is an arithmetic number, because the mean of its divisors is an integer number (10521515020).

Almost surely, 2^21043030039 is an apocalyptic number.

21043030039 is a deficient number, since it is larger than the sum of its proper divisors (1).

21043030039 is an equidigital number, since it uses as much as digits as its factorization.

21043030039 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1944, while the sum is 25.

The spelling of 21043030039 in words is "twenty-one billion, forty-three million, thirty thousand, thirty-nine".