42378257 has 2 divisors, whose sum is σ = 42378258. Its totient is φ = 42378256.

The previous prime is 42378247. The next prime is 42378269. The reversal of 42378257 is 75287324.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 24196561 + 18181696 = 4919^2 + 4264^2 .

It is a cyclic number.

It is not a de Polignac number, because 42378257 - 2⁴ = 42378241 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 42378257.

It is not a weakly prime, because it can be changed into another prime (42378247) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 21189128 + 21189129.

It is an arithmetic number, because the mean of its divisors is an integer number (21189129).

Almost surely, 2^42378257 is an apocalyptic number.

It is an amenable number.

42378257 is a deficient number, since it is larger than the sum of its proper divisors (1).

42378257 is an equidigital number, since it uses as much as digits as its factorization.

42378257 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 94080, while the sum is 38.

The square root of 42378257 is about 6509.8584470017. The cubic root of 42378257 is about 348.6430643823.

The spelling of 42378257 in words is "forty-two million, three hundred seventy-eight thousand, two hundred fifty-seven".