31221213033320 has 32 divisors (see below), whose sum is σ = 70248189060000. Its totient is φ = 12488403482688.

The previous prime is 31221213033313. The next prime is 31221213033349. The reversal of 31221213033320 is 2333031212213.

It is a self number, because there is not a number n which added to its sum of digits gives 31221213033320.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3831431 + ... + 8781929.

It is an arithmetic number, because the mean of its divisors is an integer number (2195255908125).

Almost surely, 2^{31221213033320} is an apocalyptic number.

It is an amenable number.

31221213033320 is an abundant number, since it is smaller than the sum of its proper divisors (39026976026680).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

31221213033320 is a wasteful number, since it uses less digits than its factorization.

31221213033320 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5108177 (or 5108173 counting only the distinct ones).

The product of its (nonzero) digits is 3888, while the sum is 26.

Adding to 31221213033320 its reverse (2333031212213), we get a palindrome (33554244245533).

The spelling of 31221213033320 in words is "thirty-one trillion, two hundred twenty-one billion, two hundred thirteen million, thirty-three thousand, three hundred twenty".