31109689 has 6 divisors (see below), whose sum is σ = 33687006. Its totient is φ = 28716480.

The previous prime is 31109681. The next prime is 31109713. The reversal of 31109689 is 98690113.

It can be written as a sum of positive squares in 3 ways, for example, as 672400 + 30437289 = 820^2 + 5517^2 .

It is not a de Polignac number, because 31109689 - 2³ = 31109681 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (31109681) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 91872 + ... + 92209.

It is an arithmetic number, because the mean of its divisors is an integer number (5614501).

Almost surely, 2^31109689 is an apocalyptic number.

It is an amenable number.

31109689 is a deficient number, since it is larger than the sum of its proper divisors (2577317).

31109689 is a wasteful number, since it uses less digits than its factorization.

31109689 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 184107 (or 184094 counting only the distinct ones).

The product of its (nonzero) digits is 11664, while the sum is 37.

The square root of 31109689 is about 5577.6060276789. The cubic root of 31109689 is about 314.5081397445.

The spelling of 31109689 in words is "thirty-one million, one hundred nine thousand, six hundred eighty-nine".