605155781 has 2 divisors, whose sum is σ = 605155782. Its totient is φ = 605155780.

The previous prime is 605155723. The next prime is 605155799. The reversal of 605155781 is 187551506.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 466128100 + 139027681 = 21590^2 + 11791^2 .

It is a cyclic number.

It is not a de Polignac number, because 605155781 - 2⁶ = 605155717 is a prime.

It is a super-2 number, since 2×605155781² = 732427038555439922, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (605155711) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 302577890 + 302577891.

It is an arithmetic number, because the mean of its divisors is an integer number (302577891).

Almost surely, 2^605155781 is an apocalyptic number.

It is an amenable number.

605155781 is a deficient number, since it is larger than the sum of its proper divisors (1).

605155781 is an equidigital number, since it uses as much as digits as its factorization.

605155781 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 42000, while the sum is 38.

The square root of 605155781 is about 24599.9142478180. The cubic root of 605155781 is about 845.8416417302.

The spelling of 605155781 in words is "six hundred five million, one hundred fifty-five thousand, seven hundred eighty-one".