30131221221 has 12 divisors (see below), whose sum is σ = 43528342572. Its totient is φ = 20084957376.

The previous prime is 30131221217. The next prime is 30131221319. The reversal of 30131221221 is 12212213103.

It can be written as a sum of positive squares in 2 ways, for example, as 21465473121 + 8665748100 = 146511^2 + 93090^2 .

It is not a de Polignac number, because 30131221221 - 2² = 30131221217 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 30131221194 and 30131221203.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (30131221201) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 133176 + ... + 279281.

It is an arithmetic number, because the mean of its divisors is an integer number (3627361881).

Almost surely, 2^30131221221 is an apocalyptic number.

It is an amenable number.

30131221221 is a deficient number, since it is larger than the sum of its proper divisors (13397121351).

30131221221 is a wasteful number, since it uses less digits than its factorization.

30131221221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 420580 (or 420577 counting only the distinct ones).

The product of its (nonzero) digits is 144, while the sum is 18.

Adding to 30131221221 its reverse (12212213103), we get a palindrome (42343434324).

The spelling of 30131221221 in words is "thirty billion, one hundred thirty-one million, two hundred twenty-one thousand, two hundred twenty-one".