355568161981 has 2 divisors, whose sum is σ = 355568161982. Its totient is φ = 355568161980.

The previous prime is 355568161967. The next prime is 355568162023. The reversal of 355568161981 is 189161865553.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 238764163225 + 116803998756 = 488635^2 + 341766^2 .

It is a cyclic number.

It is not a de Polignac number, because 355568161981 - 2⁹ = 355568161469 is a prime.

It is a super-2 number, since 2×355568161981² (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 (355568101981) 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, 177784080990 + 177784080991.

It is an arithmetic number, because the mean of its divisors is an integer number (177784080991).

Almost surely, 2^355568161981 is an apocalyptic number.

It is an amenable number.

355568161981 is a deficient number, since it is larger than the sum of its proper divisors (1).

355568161981 is an equidigital number, since it uses as much as digits as its factorization.

355568161981 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 7776000, while the sum is 58.

The spelling of 355568161981 in words is "three hundred fifty-five billion, five hundred sixty-eight million, one hundred sixty-one thousand, nine hundred eighty-one".