31033221222221 has 4 divisors (see below), whose sum is σ = 31353151338012. Its totient is φ = 30713291106432.

The previous prime is 31033221222197. The next prime is 31033221222271. The reversal of 31033221222221 is 12222212233013.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 23554423824100 + 7478797398121 = 4853290^2 + 2734739^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-31033221222221 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31033221222271) 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, 159965057750 + ... + 159965057943.

It is an arithmetic number, because the mean of its divisors is an integer number (7838287834503).

Almost surely, 2^{31033221222221} is an apocalyptic number.

It is an amenable number.

31033221222221 is a deficient number, since it is larger than the sum of its proper divisors (319930115791).

31033221222221 is an equidigital number, since it uses as much as digits as its factorization.

31033221222221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 319930115790.

The product of its (nonzero) digits is 3456, while the sum is 26.

Adding to 31033221222221 its reverse (12222212233013), we get a palindrome (43255433455234).

The spelling of 31033221222221 in words is "thirty-one trillion, thirty-three billion, two hundred twenty-one million, two hundred twenty-two thousand, two hundred twenty-one".