31323033221 has 4 divisors (see below), whose sum is σ = 31328651244. Its totient is φ = 31317415200.

The previous prime is 31323033149. The next prime is 31323033229. The reversal of 31323033221 is 12233032313.

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 8669472100 + 22653561121 = 93110^2 + 150511^2 .

It is a cyclic number.

It is not a de Polignac number, because 31323033221 - 2¹⁰ = 31323032197 is a prime.

It is a super-2 number, since 2×31323033221² (a number of 22 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31323033229) 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, 2800640 + ... + 2811801.

It is an arithmetic number, because the mean of its divisors is an integer number (7832162811).

Almost surely, 2^31323033221 is an apocalyptic number.

It is an amenable number.

31323033221 is a deficient number, since it is larger than the sum of its proper divisors (5618023).

31323033221 is an equidigital number, since it uses as much as digits as its factorization.

31323033221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5618022.

The product of its (nonzero) digits is 1944, while the sum is 23.

Adding to 31323033221 its reverse (12233032313), we get a palindrome (43556065534).

The spelling of 31323033221 in words is "thirty-one billion, three hundred twenty-three million, thirty-three thousand, two hundred twenty-one".