311805454781 has 2 divisors, whose sum is σ = 311805454782. Its totient is φ = 311805454780.

The previous prime is 311805454759. The next prime is 311805454819. The reversal of 311805454781 is 187454508113.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 290673017881 + 21132436900 = 539141^2 + 145370^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-311805454781 is a prime.

It is a super-2 number, since 2×311805454781² (a number of 24 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (311805454721) 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, 155902727390 + 155902727391.

It is an arithmetic number, because the mean of its divisors is an integer number (155902727391).

Almost surely, 2^311805454781 is an apocalyptic number.

It is an amenable number.

311805454781 is a deficient number, since it is larger than the sum of its proper divisors (1).

311805454781 is an equidigital number, since it uses as much as digits as its factorization.

311805454781 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 537600, while the sum is 47.

The spelling of 311805454781 in words is "three hundred eleven billion, eight hundred five million, four hundred fifty-four thousand, seven hundred eighty-one".