12689857 has 2 divisors, whose sum is σ = 12689858. Its totient is φ = 12689856.

The previous prime is 12689821. The next prime is 12689863. The reversal of 12689857 is 75898621.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 11999296 + 690561 = 3464^2 + 831^2 .

It is an emirp because it is prime and its reverse (75898621) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-12689857 is a prime.

It is a super-2 number, since 2×12689857² = 322064941360898, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (12689057) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6344928 + 6344929.

It is an arithmetic number, because the mean of its divisors is an integer number (6344929).

Almost surely, 2^12689857 is an apocalyptic number.

It is an amenable number.

12689857 is a deficient number, since it is larger than the sum of its proper divisors (1).

12689857 is an equidigital number, since it uses as much as digits as its factorization.

12689857 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 241920, while the sum is 46.

The square root of 12689857 is about 3562.2825547674. The cubic root of 12689857 is about 233.2485267766.

The spelling of 12689857 in words is "twelve million, six hundred eighty-nine thousand, eight hundred fifty-seven".