12665531 has 2 divisors, whose sum is σ = 12665532. Its totient is φ = 12665530.

The previous prime is 12665509. The next prime is 12665557. The reversal of 12665531 is 13556621.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 12665531 - 2⁶ = 12665467 is a prime.

It is a super-2 number, since 2×12665531² = 320831351023922, which contains 22 as substring.

It is a Sophie Germain prime.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 12665494 and 12665503.

It is not a weakly prime, because it can be changed into another prime (12665131) 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, 6332765 + 6332766.

It is an arithmetic number, because the mean of its divisors is an integer number (6332766).

Almost surely, 2^12665531 is an apocalyptic number.

12665531 is a deficient number, since it is larger than the sum of its proper divisors (1).

12665531 is an equidigital number, since it uses as much as digits as its factorization.

12665531 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 5400, while the sum is 29.

The square root of 12665531 is about 3558.8665330411. The cubic root of 12665531 is about 233.0993884228.

The spelling of 12665531 in words is "twelve million, six hundred sixty-five thousand, five hundred thirty-one".