311000211222221 has 4 divisors (see below), whose sum is σ = 312156345836700. Its totient is φ = 309844076607744.

The previous prime is 311000211222143. The next prime is 311000211222241. The reversal of 311000211222221 is 122222112000113.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 59234111176900 + 251766100045321 = 7696370^2 + 15867139^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-311000211222221 is a prime.

It is a super-2 number, since 2×311000211222221² (a number of 30 digits) contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 311000211222193 and 311000211222202.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (311000211222241) 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, 578067306836 + ... + 578067307373.

It is an arithmetic number, because the mean of its divisors is an integer number (78039086459175).

Almost surely, 2^{311000211222221} is an apocalyptic number.

It is an amenable number.

311000211222221 is a deficient number, since it is larger than the sum of its proper divisors (1156134614479).

311000211222221 is a wasteful number, since it uses less digits than its factorization.

311000211222221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1156134614478.

The product of its (nonzero) digits is 192, while the sum is 20.

Adding to 311000211222221 its reverse (122222112000113), we get a palindrome (433222323222334).

The spelling of 311000211222221 in words is "three hundred eleven trillion, two hundred eleven million, two hundred twenty-two thousand, two hundred twenty-one".