31221325021224 has 128 divisors (see below), whose sum is σ = 88494650294400. Its totient is φ = 9099599201280.

The previous prime is 31221325021219. The next prime is 31221325021231. The reversal of 31221325021224 is 42212052312213.

It is a happy number.

It is a super-2 number, since 2×31221325021224² (a number of 28 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 31221325021191 and 31221325021200.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 39809422 + ... + 40586114.

It is an arithmetic number, because the mean of its divisors is an integer number (691364455425).

Almost surely, 2^{31221325021224} is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 31221325021224, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (44247325147200).

31221325021224 is an abundant number, since it is smaller than the sum of its proper divisors (57273325273176).

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

31221325021224 is a wasteful number, since it uses less digits than its factorization.

31221325021224 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 783515 (or 783511 counting only the distinct ones).

The product of its (nonzero) digits is 11520, while the sum is 30.

Adding to 31221325021224 its reverse (42212052312213), we get a palindrome (73433377333437).

The spelling of 31221325021224 in words is "thirty-one trillion, two hundred twenty-one billion, three hundred twenty-five million, twenty-one thousand, two hundred twenty-four".