63685381 has 2 divisors, whose sum is σ = 63685382. Its totient is φ = 63685380.

The previous prime is 63685361. The next prime is 63685411. The reversal of 63685381 is 18358636.

63685381 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 42837025 + 20848356 = 6545^2 + 4566^2 .

It is a cyclic number.

It is not a de Polignac number, because 63685381 - 2⁹ = 63684869 is a prime.

It is a super-2 number, since 2×63685381² = 8111655506230322, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (63685301) 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, 31842690 + 31842691.

It is an arithmetic number, because the mean of its divisors is an integer number (31842691).

Almost surely, 2^63685381 is an apocalyptic number.

It is an amenable number.

63685381 is a deficient number, since it is larger than the sum of its proper divisors (1).

63685381 is an equidigital number, since it uses as much as digits as its factorization.

63685381 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 103680, while the sum is 40.

The square root of 63685381 is about 7980.3120866292. The cubic root of 63685381 is about 399.3434667498.

The spelling of 63685381 in words is "sixty-three million, six hundred eighty-five thousand, three hundred eighty-one".