20871729499 has 2 divisors, whose sum is σ = 20871729500. Its totient is φ = 20871729498.

The previous prime is 20871729469. The next prime is 20871729509. The reversal of 20871729499 is 99492717802.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 20871729499 - 2⁹ = 20871728987 is a prime.

It is not a weakly prime, because it can be changed into another prime (20871729409) 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, 10435864749 + 10435864750.

It is an arithmetic number, because the mean of its divisors is an integer number (10435864750).

Almost surely, 2^20871729499 is an apocalyptic number.

20871729499 is a deficient number, since it is larger than the sum of its proper divisors (1).

20871729499 is an equidigital number, since it uses as much as digits as its factorization.

20871729499 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 4572288, while the sum is 58.

The spelling of 20871729499 in words is "twenty billion, eight hundred seventy-one million, seven hundred twenty-nine thousand, four hundred ninety-nine".