73509640 has 16 divisors (see below), whose sum is σ = 165396780. Its totient is φ = 29403840.

The previous prime is 73509619. The next prime is 73509643. The reversal of 73509640 is 4690537.

73509640 is nontrivially palindromic in base 7.

It can be written as a sum of positive squares in 2 ways, for example, as 73170916 + 338724 = 8554^2 + 582^2 .

It is a junction number, because it is equal to n+sod(n) for n = 73509596 and 73509605.

It is not an unprimeable number, because it can be changed into a prime (73509643) 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, 918831 + ... + 918910.

Almost surely, 2^73509640 is an apocalyptic number.

It is an amenable number.

73509640 is an abundant number, since it is smaller than the sum of its proper divisors (91887140).

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

73509640 is a wasteful number, since it uses less digits than its factorization.

73509640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1837752 (or 1837748 counting only the distinct ones).

The product of its (nonzero) digits is 22680, while the sum is 34.

The square root of 73509640 is about 8573.7762975249. The cubic root of 73509640 is about 418.9042488106.

The spelling of 73509640 in words is "seventy-three million, five hundred nine thousand, six hundred forty".