42509418 has 64 divisors (see below), whose sum is σ = 106479360. Its totient is φ = 11031552.

The previous prime is 42509417. The next prime is 42509429. The reversal of 42509418 is 81490524.

It is not an unprimeable number, because it can be changed into a prime (42509417) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 19680 + ... + 21732.

It is an arithmetic number, because the mean of its divisors is an integer number (1663740).

Almost surely, 2^42509418 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 42509418, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (53239680).

42509418 is an abundant number, since it is smaller than the sum of its proper divisors (63969942).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

42509418 is a wasteful number, since it uses less digits than its factorization.

42509418 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2111.

The product of its (nonzero) digits is 11520, while the sum is 33.

The square root of 42509418 is about 6519.9246928166. The cubic root of 42509418 is about 349.0023781799.

The spelling of 42509418 in words is "forty-two million, five hundred nine thousand, four hundred eighteen".