311221123 has 2 divisors, whose sum is σ = 311221124. Its totient is φ = 311221122.

The previous prime is 311221111. The next prime is 311221147. The reversal of 311221123 is 321122113.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-311221123 is a prime.

It is a super-3 number, since 3×311221123³ (a number of 26 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a junction number, because it is equal to n+sod(n) for n = 311221097 and 311221106.

It is not a weakly prime, because it can be changed into another prime (311221103) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 155610561 + 155610562.

It is an arithmetic number, because the mean of its divisors is an integer number (155610562).

Almost surely, 2^311221123 is an apocalyptic number.

311221123 is a deficient number, since it is larger than the sum of its proper divisors (1).

311221123 is an equidigital number, since it uses as much as digits as its factorization.

311221123 is an evil number, because the sum of its binary digits is even.

The product of its digits is 72, while the sum is 16.

The square root of 311221123 is about 17641.4603420465. The cubic root of 311221123 is about 677.6774301427.

Adding to 311221123 its reverse (321122113), we get a palindrome (632343236).

The spelling of 311221123 in words is "three hundred eleven million, two hundred twenty-one thousand, one hundred twenty-three".