72543424406 has 4 divisors (see below), whose sum is σ = 108815136612. Its totient is φ = 36271712202.

The previous prime is 72543424381. The next prime is 72543424409. The reversal of 72543424406 is 60442434527.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 60442434527 = 149 ⋅405653923.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (72543424409) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 18135856100 + ... + 18135856103.

It is an arithmetic number, because the mean of its divisors is an integer number (27203784153).

Almost surely, 2^72543424406 is an apocalyptic number.

72543424406 is a deficient number, since it is larger than the sum of its proper divisors (36271712206).

72543424406 is a wasteful number, since it uses less digits than its factorization.

72543424406 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 36271712205.

The product of its (nonzero) digits is 645120, while the sum is 41.

The spelling of 72543424406 in words is "seventy-two billion, five hundred forty-three million, four hundred twenty-four thousand, four hundred six".