72724661 has 8 divisors (see below), whose sum is σ = 74289600. Its totient is φ = 71174880.

The previous prime is 72724649. The next prime is 72724679. The reversal of 72724661 is 16642727.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-72724661 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (72724601) 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, 6185 + ... + 13553.

It is an arithmetic number, because the mean of its divisors is an integer number (9286200).

Almost surely, 2^72724661 is an apocalyptic number.

72724661 is a gapful number since it is divisible by the number (71) formed by its first and last digit.

It is an amenable number.

72724661 is a deficient number, since it is larger than the sum of its proper divisors (1564939).

72724661 is a wasteful number, since it uses less digits than its factorization.

72724661 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7579.

The product of its digits is 28224, while the sum is 35.

The square root of 72724661 is about 8527.8755267652. The cubic root of 72724661 is about 417.4078078196.

The spelling of 72724661 in words is "seventy-two million, seven hundred twenty-four thousand, six hundred sixty-one".