12261981077 has 2 divisors, whose sum is σ = 12261981078. Its totient is φ = 12261981076.

The previous prime is 12261981029. The next prime is 12261981097. The reversal of 12261981077 is 77018916221.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 11993316196 + 268664881 = 109514^2 + 16391^2 .

It is a cyclic number.

It is not a de Polignac number, because 12261981077 - 2¹⁰ = 12261980053 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (12261981097) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6130990538 + 6130990539.

It is an arithmetic number, because the mean of its divisors is an integer number (6130990539).

Almost surely, 2^12261981077 is an apocalyptic number.

It is an amenable number.

12261981077 is a deficient number, since it is larger than the sum of its proper divisors (1).

12261981077 is an equidigital number, since it uses as much as digits as its factorization.

12261981077 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 84672, while the sum is 44.

The spelling of 12261981077 in words is "twelve billion, two hundred sixty-one million, nine hundred eighty-one thousand, seventy-seven".