13878257 has 4 divisors (see below), whose sum is σ = 13932516. Its totient is φ = 13824000.

The previous prime is 13878229. The next prime is 13878281. The reversal of 13878257 is 75287831.

13878257 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 75287831 = 4733 ⋅15907.

It can be written as a sum of positive squares in 2 ways, for example, as 9388096 + 4490161 = 3064^2 + 2119^2 .

It is a cyclic number.

It is not a de Polignac number, because 13878257 - 2¹⁰ = 13877233 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (13878217) 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, 26744 + ... + 27257.

It is an arithmetic number, because the mean of its divisors is an integer number (3483129).

Almost surely, 2^13878257 is an apocalyptic number.

It is an amenable number.

13878257 is a deficient number, since it is larger than the sum of its proper divisors (54259).

13878257 is an equidigital number, since it uses as much as digits as its factorization.

13878257 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 54258.

The product of its digits is 94080, while the sum is 41.

The square root of 13878257 is about 3725.3532718388. The cubic root of 13878257 is about 240.3135773785.

The spelling of 13878257 in words is "thirteen million, eight hundred seventy-eight thousand, two hundred fifty-seven".