204123253181 has 2 divisors, whose sum is σ = 204123253182. Its totient is φ = 204123253180.

The previous prime is 204123253177. The next prime is 204123253249. The reversal of 204123253181 is 181352321402.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 199063207225 + 5060045956 = 446165^2 + 71134^2 .

It is a cyclic number.

It is not a de Polignac number, because 204123253181 - 2² = 204123253177 is a prime.

It is a super-2 number, since 2×204123253181² (a number of 23 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (204123253141) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 102061626590 + 102061626591.

It is an arithmetic number, because the mean of its divisors is an integer number (102061626591).

Almost surely, 2^204123253181 is an apocalyptic number.

It is an amenable number.

204123253181 is a deficient number, since it is larger than the sum of its proper divisors (1).

204123253181 is an equidigital number, since it uses as much as digits as its factorization.

204123253181 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 11520, while the sum is 32.

Adding to 204123253181 its reverse (181352321402), we get a palindrome (385475574583).

The spelling of 204123253181 in words is "two hundred four billion, one hundred twenty-three million, two hundred fifty-three thousand, one hundred eighty-one".