31644161 has 4 divisors (see below), whose sum is σ = 32044800. Its totient is φ = 31243524.

The previous prime is 31644143. The next prime is 31644163. The reversal of 31644161 is 16144613.

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 a cyclic number.

It is not a de Polignac number, because 31644161 - 2²² = 27449857 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 31644161.

It is not an unprimeable number, because it can be changed into a prime (31644163) 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, 200201 + ... + 200358.

It is an arithmetic number, because the mean of its divisors is an integer number (8011200).

Almost surely, 2^31644161 is an apocalyptic number.

It is an amenable number.

31644161 is a deficient number, since it is larger than the sum of its proper divisors (400639).

31644161 is an equidigital number, since it uses as much as digits as its factorization.

31644161 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 400638.

The product of its digits is 1728, while the sum is 26.

The square root of 31644161 is about 5625.3143023301. The cubic root of 31644161 is about 316.2990312830.

Adding to 31644161 its reverse (16144613), we get a palindrome (47788774).

The spelling of 31644161 in words is "thirty-one million, six hundred forty-four thousand, one hundred sixty-one".