21002019959 has 2 divisors, whose sum is σ = 21002019960. Its totient is φ = 21002019958.

The previous prime is 21002019917. The next prime is 21002020043. The reversal of 21002019959 is 95991020012.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21002019959 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21002019659) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10501009979 + 10501009980.

It is an arithmetic number, because the mean of its divisors is an integer number (10501009980).

Almost surely, 2^21002019959 is an apocalyptic number.

21002019959 is a deficient number, since it is larger than the sum of its proper divisors (1).

21002019959 is an equidigital number, since it uses as much as digits as its factorization.

21002019959 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 14580, while the sum is 38.

The spelling of 21002019959 in words is "twenty-one billion, two million, nineteen thousand, nine hundred fifty-nine".