8261636885 has 12 divisors (see below), whose sum is σ = 10013156004. Its totient is φ = 6543830400.

The previous prime is 8261636881. The next prime is 8261636917. The reversal of 8261636885 is 5886361628.

It can be written as a sum of positive squares in 6 ways, for example, as 1967277316 + 6294359569 = 44354^2 + 79337^2 .

It is not a de Polignac number, because 8261636885 - 2² = 8261636881 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (8261636881) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 29984 + ... + 131993.

It is an arithmetic number, because the mean of its divisors is an integer number (834429667).

Almost surely, 2^8261636885 is an apocalyptic number.

It is an amenable number.

8261636885 is a deficient number, since it is larger than the sum of its proper divisors (1751519119).

8261636885 is a wasteful number, since it uses less digits than its factorization.

8261636885 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 162184 (or 162083 counting only the distinct ones).

The product of its digits is 3317760, while the sum is 53.

The square root of 8261636885 is about 90893.5469931722. The cubic root of 8261636885 is about 2021.5696133708.

The spelling of 8261636885 in words is "eight billion, two hundred sixty-one million, six hundred thirty-six thousand, eight hundred eighty-five".