12400457 has 2 divisors, whose sum is σ = 12400458. Its totient is φ = 12400456.

The previous prime is 12400441. The next prime is 12400489. The reversal of 12400457 is 75400421.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 9174841 + 3225616 = 3029^2 + 1796^2 .

It is an emirp because it is prime and its reverse (75400421) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 12400457 - 2⁴ = 12400441 is a prime.

It is not a weakly prime, because it can be changed into another prime (12400757) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6200228 + 6200229.

It is an arithmetic number, because the mean of its divisors is an integer number (6200229).

Almost surely, 2^12400457 is an apocalyptic number.

It is an amenable number.

12400457 is a deficient number, since it is larger than the sum of its proper divisors (1).

12400457 is an equidigital number, since it uses as much as digits as its factorization.

12400457 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1120, while the sum is 23.

The square root of 12400457 is about 3521.4282613735. The cubic root of 12400457 is about 231.4617488779.

Adding to 12400457 its reverse (75400421), we get a palindrome (87800878).

The spelling of 12400457 in words is "twelve million, four hundred thousand, four hundred fifty-seven".