31221541022406 has 128 divisors (see below), whose sum is σ = 76724826587136. Its totient is φ = 8275286954880.

The previous prime is 31221541022393. The next prime is 31221541022417. The reversal of 31221541022406 is 60422014512213.

It is a congruent number.

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 63 ways as a sum of consecutive naturals, for example, 9711381 + ... + 12520143.

It is an arithmetic number, because the mean of its divisors is an integer number (599412707712).

Almost surely, 2^{31221541022406} is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 31221541022406, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (38362413293568).

31221541022406 is an abundant number, since it is smaller than the sum of its proper divisors (45503285564730).

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

31221541022406 is a wasteful number, since it uses less digits than its factorization.

31221541022406 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2809146.

The product of its (nonzero) digits is 23040, while the sum is 33.

Adding to 31221541022406 its reverse (60422014512213), we get a palindrome (91643555534619).

The spelling of 31221541022406 in words is "thirty-one trillion, two hundred twenty-one billion, five hundred forty-one million, twenty-two thousand, four hundred six".