12820420571 has 4 divisors (see below), whose sum is σ = 14651909232. Its totient is φ = 10988931912.

The previous prime is 12820420549. The next prime is 12820420597. The reversal of 12820420571 is 17502402821.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 17502402821 = 773 ⋅22642177.

It is not a de Polignac number, because 12820420571 - 2³⁰ = 11746678747 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (12820420471) 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 in 3 ways as a sum of consecutive naturals, for example, 915744320 + ... + 915744333.

It is an arithmetic number, because the mean of its divisors is an integer number (3662977308).

Almost surely, 2^12820420571 is an apocalyptic number.

12820420571 is a deficient number, since it is larger than the sum of its proper divisors (1831488661).

12820420571 is an equidigital number, since it uses as much as digits as its factorization.

12820420571 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1831488660.

The product of its (nonzero) digits is 8960, while the sum is 32.

The spelling of 12820420571 in words is "twelve billion, eight hundred twenty million, four hundred twenty thousand, five hundred seventy-one".