31220344221 has 32 divisors (see below), whose sum is σ = 46473965568. Its totient is φ = 18480363840.

The previous prime is 31220344213. The next prime is 31220344237. The reversal of 31220344221 is 12244302213.

It is a happy number.

It is not a de Polignac number, because 31220344221 - 2³ = 31220344213 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 31220344191 and 31220344200.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31220344241) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 734671 + ... + 776003.

It is an arithmetic number, because the mean of its divisors is an integer number (1452311424).

Almost surely, 2^31220344221 is an apocalyptic number.

It is an amenable number.

31220344221 is a deficient number, since it is larger than the sum of its proper divisors (15253621347).

31220344221 is a wasteful number, since it uses less digits than its factorization.

31220344221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 41881.

The product of its (nonzero) digits is 2304, while the sum is 24.

Adding to 31220344221 its reverse (12244302213), we get a palindrome (43464646434).

The spelling of 31220344221 in words is "thirty-one billion, two hundred twenty million, three hundred forty-four thousand, two hundred twenty-one".