40643461638 has 32 divisors (see below), whose sum is σ = 97266405600. Its totient is φ = 12505680288.

The previous prime is 40643461631. The next prime is 40643461673. The reversal of 40643461638 is 83616434604.

It is a happy number.

40643461638 is a `hidden beast` number, since 4 + 0 + 6 + 4 + 3 + 4 + 6 + 1 + 638 = 666.

It is a junction number, because it is equal to n+sod(n) for n = 40643461593 and 40643461602.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (40643461631) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 28947633 + ... + 28949036.

It is an arithmetic number, because the mean of its divisors is an integer number (3039575175).

Almost surely, 2^40643461638 is an apocalyptic number.

40643461638 is an abundant number, since it is smaller than the sum of its proper divisors (56622943962).

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

40643461638 is a wasteful number, since it uses less digits than its factorization.

40643461638 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 57896693 (or 57896687 counting only the distinct ones).

The product of its (nonzero) digits is 995328, while the sum is 45.

The spelling of 40643461638 in words is "forty billion, six hundred forty-three million, four hundred sixty-one thousand, six hundred thirty-eight".