640323136404 has 144 divisors (see below), whose sum is σ = 1876920304896. Its totient is φ = 180272332800.

The previous prime is 640323136373. The next prime is 640323136451. The reversal of 640323136404 is 404631323046.

640323136404 is a `hidden beast` number, since 6 + 4 + 0 + 3 + 2 + 3 + 1 + 3 + 640 + 4 = 666.

640323136404 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 35721364 + ... + 35739284.

It is an arithmetic number, because the mean of its divisors is an integer number (13034168784).

Almost surely, 2^640323136404 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 640323136404, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (938460152448).

640323136404 is an abundant number, since it is smaller than the sum of its proper divisors (1236597168492).

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

640323136404 is a wasteful number, since it uses less digits than its factorization.

640323136404 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20006 (or 20001 counting only the distinct ones).

The product of its (nonzero) digits is 124416, while the sum is 36.

The spelling of 640323136404 in words is "six hundred forty billion, three hundred twenty-three million, one hundred thirty-six thousand, four hundred four".