13128457 has 4 divisors (see below), whose sum is σ = 13294720. Its totient is φ = 12962196.

The previous prime is 13128443. The next prime is 13128461. The reversal of 13128457 is 75482131.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 75482131 = 2617 ⋅28843.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-13128457 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (13128257) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 83013 + ... + 83170.

It is an arithmetic number, because the mean of its divisors is an integer number (3323680).

Almost surely, 2^13128457 is an apocalyptic number.

It is an amenable number.

13128457 is a deficient number, since it is larger than the sum of its proper divisors (166263).

13128457 is an equidigital number, since it uses as much as digits as its factorization.

13128457 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 166262.

The product of its digits is 6720, while the sum is 31.

The square root of 13128457 is about 3623.3212664626. The cubic root of 13128457 is about 235.9054071256.

The spelling of 13128457 in words is "thirteen million, one hundred twenty-eight thousand, four hundred fifty-seven".