31221331221012 has 12 divisors (see below), whose sum is σ = 72849772849056. Its totient is φ = 10407110407000.

The previous prime is 31221331221011. The next prime is 31221331221053. The reversal of 31221331221012 is 21012213312213.

It is a tau number, because it is divible by the number of its divisors (12).

It is a super-3 number, since 3×31221331221012³ (a number of 41 digits) contains 333 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31221331221011) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1300888800864 + ... + 1300888800887.

It is an arithmetic number, because the mean of its divisors is an integer number (6070814404088).

Almost surely, 2^{31221331221012} is an apocalyptic number.

It is an amenable number.

31221331221012 is an abundant number, since it is smaller than the sum of its proper divisors (41628441628044).

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

31221331221012 is a wasteful number, since it uses less digits than its factorization.

31221331221012 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2601777601758 (or 2601777601756 counting only the distinct ones).

The product of its (nonzero) digits is 864, while the sum is 24.

Adding to 31221331221012 its reverse (21012213312213), we get a palindrome (52233544533225).

The spelling of 31221331221012 in words is "thirty-one trillion, two hundred twenty-one billion, three hundred thirty-one million, two hundred twenty-one thousand, twelve".