12611250805 has 4 divisors (see below), whose sum is σ = 15133500972. Its totient is φ = 10089000640.

The previous prime is 12611250787. The next prime is 12611250809. The reversal of 12611250805 is 50805211621.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 50805211621 = 29 ⋅1751903849.

It can be written as a sum of positive squares in 2 ways, for example, as 3813186001 + 8798064804 = 61751^2 + 93798^2 .

It is a de Polignac number, because none of the positive numbers 2^k-12611250805 is a prime.

It is a super-2 number, since 2×12611250805² (a number of 21 digits) contains 22 as substring.

It is a Smith number, since the sum of its digits (31) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12611250809) 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, 1261125076 + ... + 1261125085.

It is an arithmetic number, because the mean of its divisors is an integer number (3783375243).

Almost surely, 2^12611250805 is an apocalyptic number.

It is an amenable number.

12611250805 is a deficient number, since it is larger than the sum of its proper divisors (2522250167).

12611250805 is an equidigital number, since it uses as much as digits as its factorization.

12611250805 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2522250166.

The product of its (nonzero) digits is 4800, while the sum is 31.

The spelling of 12611250805 in words is "twelve billion, six hundred eleven million, two hundred fifty thousand, eight hundred five".