13220531971 has 4 divisors (see below), whose sum is σ = 13269679200. Its totient is φ = 13171384744.

The previous prime is 13220531969. The next prime is 13220531981. The reversal of 13220531971 is 17913502231.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 17913502231 = 61 ⋅293663971.

It is a cyclic number.

It is not a de Polignac number, because 13220531971 - 2¹ = 13220531969 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (13220531941) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 24573211 + ... + 24573748.

It is an arithmetic number, because the mean of its divisors is an integer number (3317419800).

Almost surely, 2^13220531971 is an apocalyptic number.

13220531971 is a deficient number, since it is larger than the sum of its proper divisors (49147229).

13220531971 is an equidigital number, since it uses as much as digits as its factorization.

13220531971 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 49147228.

The product of its (nonzero) digits is 11340, while the sum is 34.

It can be divided in two parts, 132 and 20531971, that multiplied together give a palindrome (2710220172).

The spelling of 13220531971 in words is "thirteen billion, two hundred twenty million, five hundred thirty-one thousand, nine hundred seventy-one".