31135809 has 4 divisors (see below), whose sum is σ = 41514416. Its totient is φ = 20757204.

The previous prime is 31135799. The next prime is 31135817. The reversal of 31135809 is 90853113.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 31135809 - 2⁵ = 31135777 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (31135829) by changing a digit.

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 3 ways as a sum of consecutive naturals, for example, 5189299 + ... + 5189304.

It is an arithmetic number, because the mean of its divisors is an integer number (10378604).

Almost surely, 2^31135809 is an apocalyptic number.

It is an amenable number.

31135809 is a deficient number, since it is larger than the sum of its proper divisors (10378607).

31135809 is a wasteful number, since it uses less digits than its factorization.

31135809 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10378606.

The product of its (nonzero) digits is 3240, while the sum is 30.

The square root of 31135809 is about 5579.9470427595. The cubic root of 31135809 is about 314.5961364944.

The spelling of 31135809 in words is "thirty-one million, one hundred thirty-five thousand, eight hundred nine".