12409681 has 2 divisors, whose sum is σ = 12409682. Its totient is φ = 12409680.

The previous prime is 12409667. The next prime is 12409687. The reversal of 12409681 is 18690421.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 11833600 + 576081 = 3440^2 + 759^2 .

It is a cyclic number.

It is not a de Polignac number, because 12409681 - 2¹³ = 12401489 is a prime.

It is a super-2 number, since 2×12409681² = 308000365043522, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (12409687) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6204840 + 6204841.

It is an arithmetic number, because the mean of its divisors is an integer number (6204841).

Almost surely, 2^12409681 is an apocalyptic number.

It is an amenable number.

12409681 is a deficient number, since it is larger than the sum of its proper divisors (1).

12409681 is an equidigital number, since it uses as much as digits as its factorization.

12409681 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 3456, while the sum is 31.

The square root of 12409681 is about 3522.7377137675. The cubic root of 12409681 is about 231.5191250972.

The spelling of 12409681 in words is "twelve million, four hundred nine thousand, six hundred eighty-one".