12611821 has 2 divisors, whose sum is σ = 12611822. Its totient is φ = 12611820.

The previous prime is 12611789. The next prime is 12611831. The reversal of 12611821 is 12811621.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 8555625 + 4056196 = 2925^2 + 2014^2 .

It is a cyclic number.

It is not a de Polignac number, because 12611821 - 2⁵ = 12611789 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 12611792 and 12611801.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (12611831) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6305910 + 6305911.

It is an arithmetic number, because the mean of its divisors is an integer number (6305911).

Almost surely, 2^12611821 is an apocalyptic number.

It is an amenable number.

12611821 is a deficient number, since it is larger than the sum of its proper divisors (1).

12611821 is an equidigital number, since it uses as much as digits as its factorization.

12611821 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 192, while the sum is 22.

The square root of 12611821 is about 3551.3125742463. The cubic root of 12611821 is about 232.7694244375.

The spelling of 12611821 in words is "twelve million, six hundred eleven thousand, eight hundred twenty-one".