221020131311 has 8 divisors (see below), whose sum is σ = 252760301184. Its totient is φ = 189321427800.

The previous prime is 221020131287. The next prime is 221020131347. The reversal of 221020131311 is 113131020122.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 221020131311 - 2³⁴ = 203840262127 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 221020131311.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221020131011) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 10355165 + ... + 10376486.

It is an arithmetic number, because the mean of its divisors is an integer number (31595037648).

Almost surely, 2^221020131311 is an apocalyptic number.

221020131311 is a deficient number, since it is larger than the sum of its proper divisors (31740169873).

221020131311 is a wasteful number, since it uses less digits than its factorization.

221020131311 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20733181.

The product of its (nonzero) digits is 72, while the sum is 17.

Adding to 221020131311 its reverse (113131020122), we get a palindrome (334151151433).

The spelling of 221020131311 in words is "two hundred twenty-one billion, twenty million, one hundred thirty-one thousand, three hundred eleven".