31544411221 has 4 divisors (see below), whose sum is σ = 31626772992. Its totient is φ = 31462049452.

The previous prime is 31544411209. The next prime is 31544411273. The reversal of 31544411221 is 12211444513.

It is a happy number.

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 31544411221 - 2⁵ = 31544411189 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 31544411221.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31544417221) 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, 41180311 + ... + 41181076.

It is an arithmetic number, because the mean of its divisors is an integer number (7906693248).

Almost surely, 2^31544411221 is an apocalyptic number.

It is an amenable number.

31544411221 is a deficient number, since it is larger than the sum of its proper divisors (82361771).

31544411221 is an equidigital number, since it uses as much as digits as its factorization.

31544411221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 82361770.

The product of its digits is 3840, while the sum is 28.

Adding to 31544411221 its reverse (12211444513), we get a palindrome (43755855734).

The spelling of 31544411221 in words is "thirty-one billion, five hundred forty-four million, four hundred eleven thousand, two hundred twenty-one".