20128917829 has 2 divisors, whose sum is σ = 20128917830. Its totient is φ = 20128917828.

The previous prime is 20128917821. The next prime is 20128917833. The reversal of 20128917829 is 92871982102.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 12916322500 + 7212595329 = 113650^2 + 84927^2 .

It is a cyclic number.

It is not a de Polignac number, because 20128917829 - 2³ = 20128917821 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20128917821) 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, 10064458914 + 10064458915.

It is an arithmetic number, because the mean of its divisors is an integer number (10064458915).

Almost surely, 2^20128917829 is an apocalyptic number.

It is an amenable number.

20128917829 is a deficient number, since it is larger than the sum of its proper divisors (1).

20128917829 is an equidigital number, since it uses as much as digits as its factorization.

20128917829 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 290304, while the sum is 49.

The spelling of 20128917829 in words is "twenty billion, one hundred twenty-eight million, nine hundred seventeen thousand, eight hundred twenty-nine".