221311131 has 8 divisors (see below), whose sum is σ = 296892480. Its totient is φ = 146635272.

The previous prime is 221311121. The next prime is 221311147. The reversal of 221311131 is 131113122.

It is a happy number.

221311131 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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

It is not a de Polignac number, because 221311131 - 2⁷ = 221311003 is a prime.

It is a super-2 number, since 2×221311131² = 97957233408998322, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 221311131.

It is not an unprimeable number, because it can be changed into a prime (221311121) 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, 225801 + ... + 226778.

It is an arithmetic number, because the mean of its divisors is an integer number (37111560).

Almost surely, 2^221311131 is an apocalyptic number.

221311131 is a deficient number, since it is larger than the sum of its proper divisors (75581349).

221311131 is a wasteful number, since it uses less digits than its factorization.

221311131 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 452745.

The product of its digits is 36, while the sum is 15.

The square root of 221311131 is about 14876.5295348075. The cubic root of 221311131 is about 604.8779491062.

Adding to 221311131 its reverse (131113122), we get a palindrome (352424253).

It can be divided in two parts, 22 and 1311131, that multiplied together give a palindrome (28844882).

The spelling of 221311131 in words is "two hundred twenty-one million, three hundred eleven thousand, one hundred thirty-one".