8785812521 has 4 divisors (see below), whose sum is σ = 8792962500. Its totient is φ = 8778662544.

The previous prime is 8785812509. The next prime is 8785812523. The reversal of 8785812521 is 1252185878.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 1252185878 = 2 ⋅626092939.

It can be written as a sum of positive squares in 2 ways, for example, as 6957394921 + 1828417600 = 83411^2 + 42760^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-8785812521 is a prime.

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

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (8785812523) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3573146 + ... + 3575603.

It is an arithmetic number, because the mean of its divisors is an integer number (2198240625).

Almost surely, 2^8785812521 is an apocalyptic number.

It is an amenable number.

8785812521 is a deficient number, since it is larger than the sum of its proper divisors (7149979).

8785812521 is a wasteful number, since it uses less digits than its factorization.

8785812521 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7149978.

The product of its digits is 358400, while the sum is 47.

The square root of 8785812521 is about 93732.6651760207. The cubic root of 8785812521 is about 2063.4501301514.

The spelling of 8785812521 in words is "eight billion, seven hundred eighty-five million, eight hundred twelve thousand, five hundred twenty-one".