63581618537 has 4 divisors (see below), whose sum is σ = 63583755396. Its totient is φ = 63579481680.

The previous prime is 63581618521. The next prime is 63581618591. The reversal of 63581618537 is 73581618536.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 12380790361 + 51200828176 = 111269^2 + 226276^2 .

It is a cyclic number.

It is not a de Polignac number, because 63581618537 - 2⁴ = 63581618521 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (63581618137) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1023158 + ... + 1083519.

It is an arithmetic number, because the mean of its divisors is an integer number (15895938849).

Almost surely, 2^63581618537 is an apocalyptic number.

It is an amenable number.

63581618537 is a deficient number, since it is larger than the sum of its proper divisors (2136859).

63581618537 is a wasteful number, since it uses less digits than its factorization.

63581618537 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2136858.

The product of its digits is 3628800, while the sum is 53.

Subtracting 63581618537 from its reverse (73581618536), we obtain a palindrome (9999999999).

The spelling of 63581618537 in words is "sixty-three billion, five hundred eighty-one million, six hundred eighteen thousand, five hundred thirty-seven".