73643581440 has 1008 divisors, whose sum is σ = 304563377664. Its totient is φ = 16349921280.

The previous prime is 73643581439. The next prime is 73643581549. The reversal of 73643581440 is 4418534637.

73643581440 is a `hidden beast` number, since 7 + 3 + 64 + 3 + 581 + 4 + 4 + 0 = 666.

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 71 ways as a sum of consecutive naturals, for example, 579870657 + ... + 579870783.

It is an arithmetic number, because the mean of its divisors is an integer number (302146208).

Almost surely, 2^73643581440 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 73643581440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (152281688832).

73643581440 is an abundant number, since it is smaller than the sum of its proper divisors (230919796224).

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

73643581440 is a wasteful number, since it uses less digits than its factorization.

73643581440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 199 (or 161 counting only the distinct ones).

The product of its (nonzero) digits is 967680, while the sum is 45.

The spelling of 73643581440 in words is "seventy-three billion, six hundred forty-three million, five hundred eighty-one thousand, four hundred forty".