8118397261 has 4 divisors (see below), whose sum is σ = 8742889372. Its totient is φ = 7493905152.

The previous prime is 8118397241. The next prime is 8118397289. The reversal of 8118397261 is 1627938118.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 1458858025 + 6659539236 = 38195^2 + 81606^2 .

It is a cyclic number.

It is not a de Polignac number, because 8118397261 - 2²⁹ = 7581526349 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 (8118397201) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 312246036 + ... + 312246061.

It is an arithmetic number, because the mean of its divisors is an integer number (2185722343).

Almost surely, 2^8118397261 is an apocalyptic number.

8118397261 is the 52021-st hex number.

It is an amenable number.

8118397261 is a deficient number, since it is larger than the sum of its proper divisors (624492111).

8118397261 is a wasteful number, since it uses less digits than its factorization.

8118397261 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 624492110.

The product of its digits is 145152, while the sum is 46.

The square root of 8118397261 is about 90102.1490365241. The cubic root of 8118397261 is about 2009.8181614005.

The spelling of 8118397261 in words is "eight billion, one hundred eighteen million, three hundred ninety-seven thousand, two hundred sixty-one".