204040312981 has 2 divisors, whose sum is σ = 204040312982. Its totient is φ = 204040312980.

The previous prime is 204040312963. The next prime is 204040313051. The reversal of 204040312981 is 189213040402.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 170181000900 + 33859312081 = 412530^2 + 184009^2 .

It is a cyclic number.

It is not a de Polignac number, because 204040312981 - 2¹¹ = 204040310933 is a prime.

It is a super-2 number, since 2×204040312981² (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 (204040312921) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 102020156490 + 102020156491.

It is an arithmetic number, because the mean of its divisors is an integer number (102020156491).

Almost surely, 2^204040312981 is an apocalyptic number.

It is an amenable number.

204040312981 is a deficient number, since it is larger than the sum of its proper divisors (1).

204040312981 is an equidigital number, since it uses as much as digits as its factorization.

204040312981 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 13824, while the sum is 34.

The spelling of 204040312981 in words is "two hundred four billion, forty million, three hundred twelve thousand, nine hundred eighty-one".