42005540 has 12 divisors (see below), whose sum is σ = 88211676. Its totient is φ = 16802208.

The previous prime is 42005533. The next prime is 42005569. The reversal of 42005540 is 4550024.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 32993536 + 9012004 = 5744^2 + 3002^2 .

It is a Harshad number since it is a multiple of its sum of digits (20), and also a Moran number because the ratio is a prime number: 2100277 = 42005540 / (4 + 2 + 0 + 0 + 5 + 5 + 4 + 0).

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1050119 + ... + 1050158.

It is an arithmetic number, because the mean of its divisors is an integer number (7350973).

Almost surely, 2^42005540 is an apocalyptic number.

It is an amenable number.

42005540 is an abundant number, since it is smaller than the sum of its proper divisors (46206136).

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

42005540 is a wasteful number, since it uses less digits than its factorization.

42005540 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2100286 (or 2100284 counting only the distinct ones).

The product of its (nonzero) digits is 800, while the sum is 20.

The square root of 42005540 is about 6481.1681045935. The cubic root of 42005540 is about 347.6179472989.

Adding to 42005540 its reverse (4550024), we get a palindrome (46555564).

The spelling of 42005540 in words is "forty-two million, five thousand, five hundred forty".