21043102039 has 2 divisors, whose sum is σ = 21043102040. Its totient is φ = 21043102038.

The previous prime is 21043102021. The next prime is 21043102043. The reversal of 21043102039 is 93020134012.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21043102039 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21043102009) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10521551019 + 10521551020.

It is an arithmetic number, because the mean of its divisors is an integer number (10521551020).

Almost surely, 2^21043102039 is an apocalyptic number.

21043102039 is a deficient number, since it is larger than the sum of its proper divisors (1).

21043102039 is an equidigital number, since it uses as much as digits as its factorization.

21043102039 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1296, while the sum is 25.

The spelling of 21043102039 in words is "twenty-one billion, forty-three million, one hundred two thousand, thirty-nine".