8720136021 has 16 divisors (see below), whose sum is σ = 11757094400. Its totient is φ = 5748660720.

The previous prime is 8720136011. The next prime is 8720136037. The reversal of 8720136021 is 1206310278.

8720136021 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 8720136021 - 2¹¹ = 8720133973 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 8720136021.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (8720136001) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 52506 + ... + 142116.

It is an arithmetic number, because the mean of its divisors is an integer number (734818400).

Almost surely, 2^8720136021 is an apocalyptic number.

It is an amenable number.

8720136021 is a deficient number, since it is larger than the sum of its proper divisors (3036958379).

8720136021 is a wasteful number, since it uses less digits than its factorization.

8720136021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 89976.

The product of its (nonzero) digits is 4032, while the sum is 30.

The square root of 8720136021 is about 93381.6685490252. The cubic root of 8720136021 is about 2058.2956353035.

Adding to 8720136021 its reverse (1206310278), we get a palindrome (9926446299).

The spelling of 8720136021 in words is "eight billion, seven hundred twenty million, one hundred thirty-six thousand, twenty-one".