20843635129 has 2 divisors, whose sum is σ = 20843635130. Its totient is φ = 20843635128.

The previous prime is 20843635123. The next prime is 20843635133. The reversal of 20843635129 is 92153634802.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 10973610025 + 9870025104 = 104755^2 + 99348^2 .

It is a cyclic number.

It is not a de Polignac number, because 20843635129 - 2²⁷ = 20709417401 is a prime.

It is not a weakly prime, because it can be changed into another prime (20843635123) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10421817564 + 10421817565.

It is an arithmetic number, because the mean of its divisors is an integer number (10421817565).

Almost surely, 2^20843635129 is an apocalyptic number.

It is an amenable number.

20843635129 is a deficient number, since it is larger than the sum of its proper divisors (1).

20843635129 is an equidigital number, since it uses as much as digits as its factorization.

20843635129 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 311040, while the sum is 43.

The spelling of 20843635129 in words is "twenty billion, eight hundred forty-three million, six hundred thirty-five thousand, one hundred twenty-nine".