72443640 has 64 divisors (see below), whose sum is σ = 217971360. Its totient is φ = 19261440.

The previous prime is 72443639. The next prime is 72443663. The reversal of 72443640 is 4634427.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a junction number, because it is equal to n+sod(n) for n = 72443598 and 72443607.

It is a congruent number.

It is an unprimeable number.

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, 54180 + ... + 55500.

Almost surely, 2^72443640 is an apocalyptic number.

It is an amenable number.

72443640 is an abundant number, since it is smaller than the sum of its proper divisors (145527720).

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

72443640 is a wasteful number, since it uses less digits than its factorization.

72443640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1792 (or 1788 counting only the distinct ones).

The product of its (nonzero) digits is 16128, while the sum is 30.

The square root of 72443640 is about 8511.3829663575. The cubic root of 72443640 is about 416.8694678538.

The spelling of 72443640 in words is "seventy-two million, four hundred forty-three thousand, six hundred forty".