20436802171 has 2 divisors, whose sum is σ = 20436802172. Its totient is φ = 20436802170.

The previous prime is 20436802159. The next prime is 20436802189. The reversal of 20436802171 is 17120863402.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 20436802171 - 2²³ = 20428413563 is a prime.

It is not a weakly prime, because it can be changed into another prime (20436802121) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10218401085 + 10218401086.

It is an arithmetic number, because the mean of its divisors is an integer number (10218401086).

Almost surely, 2^20436802171 is an apocalyptic number.

20436802171 is a deficient number, since it is larger than the sum of its proper divisors (1).

20436802171 is an equidigital number, since it uses as much as digits as its factorization.

20436802171 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 16128, while the sum is 34.

The spelling of 20436802171 in words is "twenty billion, four hundred thirty-six million, eight hundred two thousand, one hundred seventy-one".