42909405 has 64 divisors (see below), whose sum is σ = 86704128. Its totient is φ = 17602560.

The previous prime is 42909401. The next prime is 42909457. The reversal of 42909405 is 50490924.

It is not a de Polignac number, because 42909405 - 2² = 42909401 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (33).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (42909401) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 111844 + ... + 112226.

It is an arithmetic number, because the mean of its divisors is an integer number (1354752).

Almost surely, 2^42909405 is an apocalyptic number.

It is an amenable number.

42909405 is an abundant number, since it is smaller than the sum of its proper divisors (43794723).

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

42909405 is a wasteful number, since it uses less digits than its factorization.

42909405 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 506.

The product of its (nonzero) digits is 12960, while the sum is 33.

The square root of 42909405 is about 6550.5270780297. The cubic root of 42909405 is about 350.0935940173.

It can be divided in two parts, 4290 and 9405, that added together give a triangular number (13695 = T₁₆₅).

The spelling of 42909405 in words is "forty-two million, nine hundred nine thousand, four hundred five".