42109440 has 80 divisors (see below), whose sum is σ = 134643168. Its totient is φ = 11227136.

The previous prime is 42109423. The next prime is 42109447. The reversal of 42109440 is 4490124.

It is a tau number, because it is divible by the number of its divisors (80).

It is a super-2 number, since 2×42109440² = 3546409874227200, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (24).

It is a self number, because there is not a number n which added to its sum of digits gives 42109440.

It is not an unprimeable number, because it can be changed into a prime (42109447) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 4939 + ... + 10421.

Almost surely, 2^42109440 is an apocalyptic number.

42109440 is a gapful number since it is divisible by the number (40) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 42109440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (67321584).

42109440 is an abundant number, since it is smaller than the sum of its proper divisors (92533728).

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

42109440 is an equidigital number, since it uses as much as digits as its factorization.

42109440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5509 (or 5493 counting only the distinct ones).

The product of its (nonzero) digits is 1152, while the sum is 24.

The square root of 42109440 is about 6489.1786845486. The cubic root of 42109440 is about 347.9043203734.

Adding to 42109440 its reverse (4490124), we get a palindrome (46599564).

The spelling of 42109440 in words is "forty-two million, one hundred nine thousand, four hundred forty".