42021544 has 8 divisors (see below), whose sum is σ = 78790410. Its totient is φ = 21010768.

The previous prime is 42021517. The next prime is 42021547. The reversal of 42021544 is 44512024.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 33200644 + 8820900 = 5762^2 + 2970^2 .

It is a tau number, because it is divible by the number of its divisors (8).

It is not an unprimeable number, because it can be changed into a prime (42021547) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2626339 + ... + 2626354.

Almost surely, 2^42021544 is an apocalyptic number.

It is an amenable number.

42021544 is a deficient number, since it is larger than the sum of its proper divisors (36768866).

42021544 is a wasteful number, since it uses less digits than its factorization.

42021544 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5252699 (or 5252695 counting only the distinct ones).

The product of its (nonzero) digits is 1280, while the sum is 22.

The square root of 42021544 is about 6482.4026409966. The cubic root of 42021544 is about 347.6620888673.

Adding to 42021544 its reverse (44512024), we get a palindrome (86533568).

The spelling of 42021544 in words is "forty-two million, twenty-one thousand, five hundred forty-four".