42904865 has 16 divisors (see below), whose sum is σ = 52254288. Its totient is φ = 33816576.

The previous prime is 42904861. The next prime is 42904909. The reversal of 42904865 is 56840924.

It can be written as a sum of positive squares in 8 ways, for example, as 5438224 + 37466641 = 2332^2 + 6121^2 .

It is a cyclic number.

It is not a de Polignac number, because 42904865 - 2² = 42904861 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (42904861) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 166817 + ... + 167073.

It is an arithmetic number, because the mean of its divisors is an integer number (3265893).

Almost surely, 2^42904865 is an apocalyptic number.

It is an amenable number.

42904865 is a deficient number, since it is larger than the sum of its proper divisors (9349423).

42904865 is a wasteful number, since it uses less digits than its factorization.

42904865 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 628.

The product of its (nonzero) digits is 69120, while the sum is 38.

The square root of 42904865 is about 6550.1805318632. The cubic root of 42904865 is about 350.0812464447.

The spelling of 42904865 in words is "forty-two million, nine hundred four thousand, eight hundred sixty-five".