221331131021 has 24 divisors (see below), whose sum is σ = 299423185152. Its totient is φ = 159199207200.

The previous prime is 221331130921. The next prime is 221331131027. The reversal of 221331131021 is 120131133122.

It is a happy number.

It is not a de Polignac number, because 221331131021 - 2²⁶ = 221264022157 is a prime.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 221331130984 and 221331131002.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221331131027) 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 23 ways as a sum of consecutive naturals, for example, 10039445 + ... + 10061466.

It is an arithmetic number, because the mean of its divisors is an integer number (12475966048).

Almost surely, 2^221331131021 is an apocalyptic number.

It is an amenable number.

221331131021 is a deficient number, since it is larger than the sum of its proper divisors (78092054131).

221331131021 is a wasteful number, since it uses less digits than its factorization.

221331131021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20100953 (or 20100942 counting only the distinct ones).

The product of its (nonzero) digits is 216, while the sum is 20.

Adding to 221331131021 its reverse (120131133122), we get a palindrome (341462264143).

The spelling of 221331131021 in words is "two hundred twenty-one billion, three hundred thirty-one million, one hundred thirty-one thousand, twenty-one".