9861312205 has 4 divisors (see below), whose sum is σ = 11833574652. Its totient is φ = 7889049760.

The previous prime is 9861312203. The next prime is 9861312211. The reversal of 9861312205 is 5022131689.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 5022131689 = 70867².

It can be written as a sum of positive squares in 2 ways, for example, as 4911626889 + 4949685316 = 70083^2 + 70354^2 .

It is not a de Polignac number, because 9861312205 - 2¹ = 9861312203 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 (9861312203) 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, 986131216 + ... + 986131225.

It is an arithmetic number, because the mean of its divisors is an integer number (2958393663).

Almost surely, 2^9861312205 is an apocalyptic number.

It is an amenable number.

9861312205 is a deficient number, since it is larger than the sum of its proper divisors (1972262447).

9861312205 is a wasteful number, since it uses less digits than its factorization.

9861312205 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1972262446.

The product of its (nonzero) digits is 25920, while the sum is 37.

The square root of 9861312205 is about 99304.1399187365. The cubic root of 9861312205 is about 2144.4284953463.

The spelling of 9861312205 in words is "nine billion, eight hundred sixty-one million, three hundred twelve thousand, two hundred five".