72305638 has 4 divisors (see below), whose sum is σ = 108458460. Its totient is φ = 36152818.

The previous prime is 72305633. The next prime is 72305657. The reversal of 72305638 is 83650327.

It is a semiprime because it is the product of two primes.

It is an alternating number because its digits alternate between odd and even.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (72305633) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 18076408 + ... + 18076411.

It is an arithmetic number, because the mean of its divisors is an integer number (27114615).

Almost surely, 2^72305638 is an apocalyptic number.

72305638 is a deficient number, since it is larger than the sum of its proper divisors (36152822).

72305638 is a wasteful number, since it uses less digits than its factorization.

72305638 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 36152821.

The product of its (nonzero) digits is 30240, while the sum is 34.

The square root of 72305638 is about 8503.2721936911. The cubic root of 72305638 is about 416.6045934908.

The spelling of 72305638 in words is "seventy-two million, three hundred five thousand, six hundred thirty-eight".