31211123101 has 2 divisors, whose sum is σ = 31211123102. Its totient is φ = 31211123100.

The previous prime is 31211123087. The next prime is 31211123143. The reversal of 31211123101 is 10132111213.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 22426560025 + 8784563076 = 149755^2 + 93726^2 .

It is a cyclic number.

It is not a de Polignac number, because 31211123101 - 2¹⁵ = 31211090333 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (31211123161) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15605561550 + 15605561551.

It is an arithmetic number, because the mean of its divisors is an integer number (15605561551).

Almost surely, 2^31211123101 is an apocalyptic number.

It is an amenable number.

31211123101 is a deficient number, since it is larger than the sum of its proper divisors (1).

31211123101 is an equidigital number, since it uses as much as digits as its factorization.

31211123101 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 36, while the sum is 16.

Adding to 31211123101 its reverse (10132111213), we get a palindrome (41343234314).

It can be divided in two parts, 3121112 and 3101, that added together give a palindrome (3124213).

The spelling of 31211123101 in words is "thirty-one billion, two hundred eleven million, one hundred twenty-three thousand, one hundred one".