20871798529 has 2 divisors, whose sum is σ = 20871798530. Its totient is φ = 20871798528.

The previous prime is 20871798487. The next prime is 20871798611. The reversal of 20871798529 is 92589717802.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 17089548529 + 3782250000 = 130727^2 + 61500^2 .

It is a cyclic number.

It is not a de Polignac number, because 20871798529 - 2¹¹ = 20871796481 is a prime.

It is not a weakly prime, because it can be changed into another prime (20871798029) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10435899264 + 10435899265.

It is an arithmetic number, because the mean of its divisors is an integer number (10435899265).

Almost surely, 2^20871798529 is an apocalyptic number.

It is an amenable number.

20871798529 is a deficient number, since it is larger than the sum of its proper divisors (1).

20871798529 is an equidigital number, since it uses as much as digits as its factorization.

20871798529 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 5080320, while the sum is 58.

The spelling of 20871798529 in words is "twenty billion, eight hundred seventy-one million, seven hundred ninety-eight thousand, five hundred twenty-nine".