20783320171 has 4 divisors (see below), whose sum is σ = 20932840600. Its totient is φ = 20633799744.

The previous prime is 20783320157. The next prime is 20783320189. The reversal of 20783320171 is 17102338702.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 20783320171 - 2⁷ = 20783320043 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20783620171) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 74760006 + ... + 74760283.

It is an arithmetic number, because the mean of its divisors is an integer number (5233210150).

Almost surely, 2^20783320171 is an apocalyptic number.

20783320171 is a deficient number, since it is larger than the sum of its proper divisors (149520429).

20783320171 is a wasteful number, since it uses less digits than its factorization.

20783320171 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 149520428.

The product of its (nonzero) digits is 14112, while the sum is 34.

Adding to 20783320171 its reverse (17102338702), we get a palindrome (37885658873).

The spelling of 20783320171 in words is "twenty billion, seven hundred eighty-three million, three hundred twenty thousand, one hundred seventy-one".