20404312129 has 2 divisors, whose sum is σ = 20404312130. Its totient is φ = 20404312128.

The previous prime is 20404312121. The next prime is 20404312151. The reversal of 20404312129 is 92121340402.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 20403265600 + 1046529 = 142840^2 + 1023^2 .

It is a cyclic number.

It is not a de Polignac number, because 20404312129 - 2³ = 20404312121 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 20404312097 and 20404312106.

It is not a weakly prime, because it can be changed into another prime (20404312121) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10202156064 + 10202156065.

It is an arithmetic number, because the mean of its divisors is an integer number (10202156065).

Almost surely, 2^20404312129 is an apocalyptic number.

It is an amenable number.

20404312129 is a deficient number, since it is larger than the sum of its proper divisors (1).

20404312129 is an equidigital number, since it uses as much as digits as its factorization.

20404312129 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 3456, while the sum is 28.

The spelling of 20404312129 in words is "twenty billion, four hundred four million, three hundred twelve thousand, one hundred twenty-nine".