42278251 has 4 divisors (see below), whose sum is σ = 42291504. Its totient is φ = 42265000.

The previous prime is 42278237. The next prime is 42278261. The reversal of 42278251 is 15287224.

It is a happy number.

42278251 is digitally balanced in base 2, 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 a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 42278251 - 2⁷ = 42278123 is a prime.

It is a Smith number, since the sum of its digits (31) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (42278231) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1401 + ... + 9301.

It is an arithmetic number, because the mean of its divisors is an integer number (10572876).

Almost surely, 2^42278251 is an apocalyptic number.

42278251 is a deficient number, since it is larger than the sum of its proper divisors (13253).

42278251 is an equidigital number, since it uses as much as digits as its factorization.

42278251 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13252.

The product of its digits is 8960, while the sum is 31.

The square root of 42278251 is about 6502.1727906908. The cubic root of 42278251 is about 348.3686008313.

The spelling of 42278251 in words is "forty-two million, two hundred seventy-eight thousand, two hundred fifty-one".