505223131981 has 2 divisors, whose sum is σ = 505223131982. Its totient is φ = 505223131980.

The previous prime is 505223131957. The next prime is 505223132023. The reversal of 505223131981 is 189131322505.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 499502630025 + 5720501956 = 706755^2 + 75634^2 .

It is a cyclic number.

It is not a de Polignac number, because 505223131981 - 2³¹ = 503075648333 is a prime.

It is a super-2 number, since 2×505223131981² (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 (505223131901) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 252611565990 + 252611565991.

It is an arithmetic number, because the mean of its divisors is an integer number (252611565991).

Almost surely, 2^505223131981 is an apocalyptic number.

It is an amenable number.

505223131981 is a deficient number, since it is larger than the sum of its proper divisors (1).

505223131981 is an equidigital number, since it uses as much as digits as its factorization.

505223131981 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 64800, while the sum is 40.

The spelling of 505223131981 in words is "five hundred five billion, two hundred twenty-three million, one hundred thirty-one thousand, nine hundred eighty-one".