63681889 has 2 divisors, whose sum is σ = 63681890. Its totient is φ = 63681888.

The previous prime is 63681853. The next prime is 63681953. The reversal of 63681889 is 98818636.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 41667025 + 22014864 = 6455^2 + 4692^2 .

It is a cyclic number.

It is not a de Polignac number, because 63681889 - 2¹⁵ = 63649121 is a prime.

It is not a weakly prime, because it can be changed into another prime (63681829) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 31840944 + 31840945.

It is an arithmetic number, because the mean of its divisors is an integer number (31840945).

Almost surely, 2^63681889 is an apocalyptic number.

It is an amenable number.

63681889 is a deficient number, since it is larger than the sum of its proper divisors (1).

63681889 is an equidigital number, since it uses as much as digits as its factorization.

63681889 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 497664, while the sum is 49.

The square root of 63681889 is about 7980.0932951940. The cubic root of 63681889 is about 399.3361676761.

The spelling of 63681889 in words is "sixty-three million, six hundred eighty-one thousand, eight hundred eighty-nine".