42084021 has 8 divisors (see below), whose sum is σ = 64128064. Its totient is φ = 24048000.

The previous prime is 42084001. The next prime is 42084023. The reversal of 42084021 is 12048024.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 42084021 - 2¹⁹ = 41559733 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (21), and also a Moran number because the ratio is a prime number: 2004001 = 42084021 / (4 + 2 + 0 + 8 + 4 + 0 + 2 + 1).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (42084023) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1001980 + ... + 1002021.

It is an arithmetic number, because the mean of its divisors is an integer number (8016008).

Almost surely, 2^42084021 is an apocalyptic number.

It is an amenable number.

42084021 is a deficient number, since it is larger than the sum of its proper divisors (22044043).

42084021 is a wasteful number, since it uses less digits than its factorization.

42084021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2004011.

The product of its (nonzero) digits is 512, while the sum is 21.

The square root of 42084021 is about 6487.2198205395. The cubic root of 42084021 is about 347.8343031363.

The spelling of 42084021 in words is "forty-two million, eighty-four thousand, twenty-one".