63712993681 has 4 divisors (see below), whose sum is σ = 63724813092. Its totient is φ = 63701174272.

The previous prime is 63712993667. The next prime is 63712993733. The reversal of 63712993681 is 18639921736.

63712993681 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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 62558013456 + 1154980225 = 250116^2 + 33985^2 .

It is a cyclic number.

It is not a de Polignac number, because 63712993681 - 2¹³ = 63712985489 is a prime.

It is a super-2 number, since 2×63712993681² (a number of 22 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (63712993181) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5901616 + ... + 5912401.

It is an arithmetic number, because the mean of its divisors is an integer number (15931203273).

Almost surely, 2^63712993681 is an apocalyptic number.

It is an amenable number.

63712993681 is a deficient number, since it is larger than the sum of its proper divisors (11819411).

63712993681 is a wasteful number, since it uses less digits than its factorization.

63712993681 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11819410.

The product of its digits is 2939328, while the sum is 55.

The spelling of 63712993681 in words is "sixty-three billion, seven hundred twelve million, nine hundred ninety-three thousand, six hundred eighty-one".