63009981 has 10 divisors (see below), whose sum is σ = 94126142. Its totient is φ = 42006600.

The previous prime is 63009977. The next prime is 63009983. The reversal of 63009981 is 18990036.

It can be written as a sum of positive squares in only one way, i.e., 53144100 + 9865881 = 7290^2 + 3141^2 .

It is not a de Polignac number, because 63009981 - 2² = 63009977 is a prime.

It is a super-2 number, since 2×63009981² = 7940515411240722, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (63009983) by changing a digit.

It is a polite number, since it can be written in 9 ways as a sum of consecutive naturals, for example, 388870 + ... + 389031.

Almost surely, 2^63009981 is an apocalyptic number.

It is an amenable number.

63009981 is a deficient number, since it is larger than the sum of its proper divisors (31116161).

63009981 is an equidigital number, since it uses as much as digits as its factorization.

63009981 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 777913 (or 777904 counting only the distinct ones).

The product of its (nonzero) digits is 11664, while the sum is 36.

The square root of 63009981 is about 7937.8826521938. The cubic root of 63009981 is about 397.9267328917.

The spelling of 63009981 in words is "sixty-three million, nine thousand, nine hundred eighty-one".