42609840 has 160 divisors (see below), whose sum is σ = 162656256. Its totient is φ = 8985600.

The previous prime is 42609821. The next prime is 42609857. The reversal of 42609840 is 4890624.

It is a super-3 number, since 3×42609840³ (a number of 24 digits) contains 333 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 20865 + ... + 22815.

Almost surely, 2^42609840 is an apocalyptic number.

42609840 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 42609840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (81328128).

42609840 is an abundant number, since it is smaller than the sum of its proper divisors (120046416).

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

42609840 is a wasteful number, since it uses less digits than its factorization.

42609840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1987 (or 1981 counting only the distinct ones).

The product of its (nonzero) digits is 13824, while the sum is 33.

The square root of 42609840 is about 6527.6213125456. The cubic root of 42609840 is about 349.2769836399.

The spelling of 42609840 in words is "forty-two million, six hundred nine thousand, eight hundred forty".