63591318981 has 6 divisors (see below), whose sum is σ = 91854127430. Its totient is φ = 42394212648.

The previous prime is 63591318953. The next prime is 63591318997. The reversal of 63591318981 is 18981319536.

63591318981 is a `hidden beast` number, since 6 + 359 + 131 + 89 + 81 = 666.

It can be written as a sum of positive squares in only one way, i.e., 53530225956 + 10061093025 = 231366^2 + 100305^2 .

It is not a de Polignac number, because 63591318981 - 2⁵ = 63591318949 is a prime.

It is a super-2 number, since 2×63591318981² (a number of 22 digits) 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 (63591318181) 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 in 5 ways as a sum of consecutive naturals, for example, 3532851046 + ... + 3532851063.

Almost surely, 2^63591318981 is an apocalyptic number.

It is an amenable number.

63591318981 is a deficient number, since it is larger than the sum of its proper divisors (28262808449).

63591318981 is a wasteful number, since it uses less digits than its factorization.

63591318981 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7065702115 (or 7065702112 counting only the distinct ones).

The product of its digits is 1399680, while the sum is 54.

The spelling of 63591318981 in words is "sixty-three billion, five hundred ninety-one million, three hundred eighteen thousand, nine hundred eighty-one".