42257405 has 4 divisors (see below), whose sum is σ = 50708892. Its totient is φ = 33805920.

The previous prime is 42257401. The next prime is 42257431. The reversal of 42257405 is 50475224.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 18335524 + 23921881 = 4282^2 + 4891^2 .

It is not a de Polignac number, because 42257405 - 2² = 42257401 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (42257401) 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, 4225736 + ... + 4225745.

It is an arithmetic number, because the mean of its divisors is an integer number (12677223).

Almost surely, 2^42257405 is an apocalyptic number.

It is an amenable number.

42257405 is a deficient number, since it is larger than the sum of its proper divisors (8451487).

42257405 is an equidigital number, since it uses as much as digits as its factorization.

42257405 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8451486.

The product of its (nonzero) digits is 11200, while the sum is 29.

The square root of 42257405 is about 6500.5695904282. The cubic root of 42257405 is about 348.3113350932.

The spelling of 42257405 in words is "forty-two million, two hundred fifty-seven thousand, four hundred five".