1805340255881 has 2 divisors, whose sum is σ = 1805340255882. Its totient is φ = 1805340255880.

The previous prime is 1805340255811. The next prime is 1805340255889. The reversal of 1805340255881 is 1885520435081.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1308186937600 + 497153318281 = 1143760^2 + 705091^2 .

It is an emirp because it is prime and its reverse (1885520435081) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1805340255881 - 2¹⁴ = 1805340239497 is a prime.

It is a super-2 number, since 2×1805340255881² (a number of 25 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (1805340255889) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 902670127940 + 902670127941.

It is an arithmetic number, because the mean of its divisors is an integer number (902670127941).

Almost surely, 2^{1805340255881} is an apocalyptic number.

It is an amenable number.

1805340255881 is a deficient number, since it is larger than the sum of its proper divisors (1).

1805340255881 is an equidigital number, since it uses as much as digits as its factorization.

1805340255881 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1536000, while the sum is 50.

The spelling of 1805340255881 in words is "one trillion, eight hundred five billion, three hundred forty million, two hundred fifty-five thousand, eight hundred eighty-one".