311101221 has 4 divisors (see below), whose sum is σ = 414801632. Its totient is φ = 207400812.

The previous prime is 311101201. The next prime is 311101283. The reversal of 311101221 is 122101113.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 311101221 - 2⁷ = 311101093 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 311101197 and 311101206.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (311101201) 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, 51850201 + ... + 51850206.

It is an arithmetic number, because the mean of its divisors is an integer number (103700408).

Almost surely, 2^311101221 is an apocalyptic number.

It is an amenable number.

311101221 is a deficient number, since it is larger than the sum of its proper divisors (103700411).

311101221 is a wasteful number, since it uses less digits than its factorization.

311101221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 103700410.

The product of its (nonzero) digits is 12, while the sum is 12.

The square root of 311101221 is about 17638.0617132382. The cubic root of 311101221 is about 677.5903909389.

Adding to 311101221 its reverse (122101113), we get a palindrome (433202334).

The spelling of 311101221 in words is "three hundred eleven million, one hundred one thousand, two hundred twenty-one".