12669561 has 16 divisors (see below), whose sum is σ = 19758400. Its totient is φ = 8001504.

The previous prime is 12669557. The next prime is 12669571. The reversal of 12669561 is 16596621.

It is not a de Polignac number, because 12669561 - 2² = 12669557 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (12669511) 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 in 15 ways as a sum of consecutive naturals, for example, 11836 + ... + 12861.

It is an arithmetic number, because the mean of its divisors is an integer number (1234900).

Almost surely, 2^12669561 is an apocalyptic number.

It is an amenable number.

12669561 is a deficient number, since it is larger than the sum of its proper divisors (7088839).

12669561 is a wasteful number, since it uses less digits than its factorization.

12669561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 24725 (or 24719 counting only the distinct ones).

The product of its digits is 19440, while the sum is 36.

The square root of 12669561 is about 3559.4326795151. The cubic root of 12669561 is about 233.1241088213.

It can be divided in two parts, 126695 and 61, that added together give a triangular number (126756 = T₅₀₃).

The spelling of 12669561 in words is "twelve million, six hundred sixty-nine thousand, five hundred sixty-one".