72668521 has 8 divisors (see below), whose sum is σ = 76620320. Its totient is φ = 68729472.

The previous prime is 72668509. The next prime is 72668537. The reversal of 72668521 is 12586627.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 72668521 - 2⁹ = 72668009 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (72668501) by changing a digit.

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 7 ways as a sum of consecutive naturals, for example, 9946 + ... + 15628.

It is an arithmetic number, because the mean of its divisors is an integer number (9577540).

Almost surely, 2^72668521 is an apocalyptic number.

It is an amenable number.

72668521 is a deficient number, since it is larger than the sum of its proper divisors (3951799).

72668521 is a wasteful number, since it uses less digits than its factorization.

72668521 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6375.

The product of its digits is 40320, while the sum is 37.

The square root of 72668521 is about 8524.5833329260. The cubic root of 72668521 is about 417.3003738058.

The spelling of 72668521 in words is "seventy-two million, six hundred sixty-eight thousand, five hundred twenty-one".