31606109 has 4 divisors (see below), whose sum is σ = 31855104. Its totient is φ = 31357116.

The previous prime is 31606097. The next prime is 31606181. The reversal of 31606109 is 90160613.

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, and also an emirpimes, since its reverse is a distinct semiprime: 90160613 = 521 ⋅173053.

It is a cyclic number.

It is not a de Polignac number, because 31606109 - 2¹⁶ = 31540573 is a prime.

It is a super-2 number, since 2×31606109² = 1997892252239762, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31603109) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 124307 + ... + 124560.

It is an arithmetic number, because the mean of its divisors is an integer number (7963776).

Almost surely, 2^31606109 is an apocalyptic number.

It is an amenable number.

31606109 is a deficient number, since it is larger than the sum of its proper divisors (248995).

31606109 is a wasteful number, since it uses less digits than its factorization.

31606109 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 248994.

The product of its (nonzero) digits is 972, while the sum is 26.

The square root of 31606109 is about 5621.9310739282. The cubic root of 31606109 is about 316.1721975805.

The spelling of 31606109 in words is "thirty-one million, six hundred six thousand, one hundred nine".