72435824640 has 480 divisors, whose sum is σ = 270992161440. Its totient is φ = 18471518208.

The previous prime is 72435824633. The next prime is 72435824731. The reversal of 72435824640 is 4642853427.

It is a happy number.

72435824640 is a `hidden beast` number, since 7 + 2 + 4 + 3 + 582 + 4 + 64 + 0 = 666.

It is a tau number, because it is divible by the number of its divisors (480).

It is a super-2 number, since 2×72435824640² (a number of 23 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 19075222 + ... + 19079018.

It is an arithmetic number, because the mean of its divisors is an integer number (564567003).

Almost surely, 2^72435824640 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 72435824640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (135496080720).

72435824640 is an abundant number, since it is smaller than the sum of its proper divisors (198556336800).

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

72435824640 is a wasteful number, since it uses less digits than its factorization.

72435824640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3859 (or 3830 counting only the distinct ones).

The product of its (nonzero) digits is 1290240, while the sum is 45.

The spelling of 72435824640 in words is "seventy-two billion, four hundred thirty-five million, eight hundred twenty-four thousand, six hundred forty".