31666417 has 4 divisors (see below), whose sum is σ = 31729140. Its totient is φ = 31603696.

The previous prime is 31666403. The next prime is 31666477. The reversal of 31666417 is 71466613.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 71466613 = 109 ⋅655657.

It can be written as a sum of positive squares in 2 ways, for example, as 11943936 + 19722481 = 3456^2 + 4441^2 .

It is a cyclic number.

It is not a de Polignac number, because 31666417 - 2¹⁵ = 31633649 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (31666477) 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, 30598 + ... + 31615.

It is an arithmetic number, because the mean of its divisors is an integer number (7932285).

Almost surely, 2^31666417 is an apocalyptic number.

It is an amenable number.

31666417 is a deficient number, since it is larger than the sum of its proper divisors (62723).

31666417 is an equidigital number, since it uses as much as digits as its factorization.

31666417 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 62722.

The product of its digits is 18144, while the sum is 34.

The square root of 31666417 is about 5627.2921552022. The cubic root of 31666417 is about 316.3731671457.

The spelling of 31666417 in words is "thirty-one million, six hundred sixty-six thousand, four hundred seventeen".