20001221039 has 2 divisors, whose sum is σ = 20001221040. Its totient is φ = 20001221038.

The previous prime is 20001220997. The next prime is 20001221047. The reversal of 20001221039 is 93012210002.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20001221039 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 20001221039.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20001221059) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10000610519 + 10000610520.

It is an arithmetic number, because the mean of its divisors is an integer number (10000610520).

Almost surely, 2^20001221039 is an apocalyptic number.

20001221039 is a deficient number, since it is larger than the sum of its proper divisors (1).

20001221039 is an equidigital number, since it uses as much as digits as its factorization.

20001221039 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 216, while the sum is 20.

The spelling of 20001221039 in words is "twenty billion, one million, two hundred twenty-one thousand, thirty-nine".