8698531721 has 48 divisors (see below), whose sum is σ = 10374255360. Its totient is φ = 7211913120.

The previous prime is 8698531711. The next prime is 8698531727. The reversal of 8698531721 is 1271358968.

It is not a de Polignac number, because 8698531721 - 2⁶ = 8698531657 is a prime.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 8698531721.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (8698531727) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 38319410 + ... + 38319636.

It is an arithmetic number, because the mean of its divisors is an integer number (216130320).

Almost surely, 2^8698531721 is an apocalyptic number.

It is an amenable number.

8698531721 is a deficient number, since it is larger than the sum of its proper divisors (1675723639).

8698531721 is a wasteful number, since it uses less digits than its factorization.

8698531721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 434 (or 387 counting only the distinct ones).

The product of its digits is 725760, while the sum is 50.

The square root of 8698531721 is about 93265.9193971732. The cubic root of 8698531721 is about 2056.5944076170.

The spelling of 8698531721 in words is "eight billion, six hundred ninety-eight million, five hundred thirty-one thousand, seven hundred twenty-one".