31660009 has 4 divisors (see below), whose sum is σ = 31672960. Its totient is φ = 31647060.

The previous prime is 31660003. The next prime is 31660033. The reversal of 31660009 is 90006613.

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 a brilliant number, because the two primes have the same length, and also an emirpimes, since its reverse is a distinct semiprime: 90006613 = 23 ⋅3913331.

It is a cyclic number.

It is not a de Polignac number, because 31660009 - 2¹³ = 31651817 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (31660003) 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, 1569 + ... + 8110.

It is an arithmetic number, because the mean of its divisors is an integer number (7918240).

Almost surely, 2^31660009 is an apocalyptic number.

It is an amenable number.

31660009 is a deficient number, since it is larger than the sum of its proper divisors (12951).

31660009 is an equidigital number, since it uses as much as digits as its factorization.

31660009 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12950.

The product of its (nonzero) digits is 972, while the sum is 25.

The square root of 31660009 is about 5626.7227584092. The cubic root of 31660009 is about 316.3518253351.

The spelling of 31660009 in words is "thirty-one million, six hundred sixty thousand, nine".