63729635440 has 20 divisors (see below), whose sum is σ = 148171402584. Its totient is φ = 25491854144.

The previous prime is 63729635419. The next prime is 63729635449. The reversal of 63729635440 is 4453692736.

It is a tau number, because it is divible by the number of its divisors (20).

It is a super-2 number, since 2×63729635440² (a number of 22 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (63729635449) 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, 398310142 + ... + 398310301.

Almost surely, 2^63729635440 is an apocalyptic number.

It is an amenable number.

63729635440 is an abundant number, since it is smaller than the sum of its proper divisors (84441767144).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

63729635440 is a wasteful number, since it uses less digits than its factorization.

63729635440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 796620456 (or 796620450 counting only the distinct ones).

The product of its (nonzero) digits is 3265920, while the sum is 49.

The spelling of 63729635440 in words is "sixty-three billion, seven hundred twenty-nine million, six hundred thirty-five thousand, four hundred forty".