406042909 has 4 divisors (see below), whose sum is σ = 429927804. Its totient is φ = 382158016.

The previous prime is 406042883. The next prime is 406042933. The reversal of 406042909 is 909240604.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 377719225 + 28323684 = 19435^2 + 5322^2 .

It is a cyclic number.

It is not a de Polignac number, because 406042909 - 2¹⁷ = 405911837 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (406042969) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 11942422 + ... + 11942455.

It is an arithmetic number, because the mean of its divisors is an integer number (107481951).

Almost surely, 2^406042909 is an apocalyptic number.

It is an amenable number.

406042909 is a deficient number, since it is larger than the sum of its proper divisors (23884895).

406042909 is a wasteful number, since it uses less digits than its factorization.

406042909 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 23884894.

The product of its (nonzero) digits is 15552, while the sum is 34.

The square root of 406042909 is about 20150.5064204352. The cubic root of 406042909 is about 740.4981482710.

The spelling of 406042909 in words is "four hundred six million, forty-two thousand, nine hundred nine".