8638729 has 8 divisors (see below), whose sum is σ = 9544320. Its totient is φ = 7753200.

The previous prime is 8638727. The next prime is 8638733. The reversal of 8638729 is 9278368.

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 8638729 - 2¹ = 8638727 is a prime.

It is a Duffinian number.

8638729 is a lucky number.

It is not an unprimeable number, because it can be changed into a prime (8638727) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 4102 + ... + 5839.

It is an arithmetic number, because the mean of its divisors is an integer number (1193040).

Almost surely, 2^8638729 is an apocalyptic number.

It is an amenable number.

8638729 is a deficient number, since it is larger than the sum of its proper divisors (905591).

8638729 is a wasteful number, since it uses less digits than its factorization.

8638729 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10031.

The product of its digits is 145152, while the sum is 43.

The square root of 8638729 is about 2939.1714818976. The cubic root of 8638729 is about 205.1870511660.

The spelling of 8638729 in words is "eight million, six hundred thirty-eight thousand, seven hundred twenty-nine".