42120865 has 16 divisors (see below), whose sum is σ = 51955200. Its totient is φ = 32764032.

The previous prime is 42120857. The next prime is 42120877. The reversal of 42120865 is 56802124.

It is a cyclic number.

It is not a de Polignac number, because 42120865 - 2³ = 42120857 is a prime.

It is an unprimeable number.

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 15 ways as a sum of consecutive naturals, for example, 87696 + ... + 88174.

It is an arithmetic number, because the mean of its divisors is an integer number (3247200).

Almost surely, 2^42120865 is an apocalyptic number.

It is an amenable number.

42120865 is a deficient number, since it is larger than the sum of its proper divisors (9834335).

42120865 is a wasteful number, since it uses less digits than its factorization.

42120865 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 936.

The product of its (nonzero) digits is 3840, while the sum is 28.

The square root of 42120865 is about 6490.0589365583. The cubic root of 42120865 is about 347.9357816279.

Adding to 42120865 its reverse (56802124), we get a palindrome (98922989).

The spelling of 42120865 in words is "forty-two million, one hundred twenty thousand, eight hundred sixty-five".