42406440 has 64 divisors (see below), whose sum is σ = 130671360. Its totient is φ = 11001600.

The previous prime is 42406433. The next prime is 42406447. The reversal of 42406440 is 4460424.

It is an interprime number because it is at equal distance from previous prime (42406433) and next prime (42406447).

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 42406440.

It is not an unprimeable number, because it can be changed into a prime (42406447) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 336 + ... + 9215.

It is an arithmetic number, because the mean of its divisors is an integer number (2041740).

Almost surely, 2^42406440 is an apocalyptic number.

42406440 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 42406440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (65335680).

42406440 is an abundant number, since it is smaller than the sum of its proper divisors (88264920).

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

42406440 is a wasteful number, since it uses less digits than its factorization.

42406440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9602 (or 9598 counting only the distinct ones).

The product of its (nonzero) digits is 3072, while the sum is 24.

The square root of 42406440 is about 6512.0227272331. The cubic root of 42406440 is about 348.7203338031.

Adding to 42406440 its reverse (4460424), we get a palindrome (46866864).

The spelling of 42406440 in words is "forty-two million, four hundred six thousand, four hundred forty".