42021440 has 28 divisors (see below), whose sum is σ = 100064316. Its totient is φ = 16808448.

The previous prime is 42021401. The next prime is 42021509. The reversal of 42021440 is 4412024.

It can be written as a sum of positive squares in 2 ways, for example, as 12166144 + 29855296 = 3488^2 + 5464^2 .

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 65339 + ... + 65978.

Almost surely, 2^42021440 is an apocalyptic number.

42021440 is a gapful number since it is divisible by the number (40) formed by its first and last digit.

It is an amenable number.

42021440 is an abundant number, since it is smaller than the sum of its proper divisors (58042876).

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

42021440 is a wasteful number, since it uses less digits than its factorization.

42021440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 131334 (or 131324 counting only the distinct ones).

The product of its (nonzero) digits is 256, while the sum is 17.

The square root of 42021440 is about 6482.3946192746. The cubic root of 42021440 is about 347.6618020550.

Adding to 42021440 its reverse (4412024), we get a palindrome (46433464).

The spelling of 42021440 in words is "forty-two million, twenty-one thousand, four hundred forty".