31232122021 has 4 divisors (see below), whose sum is σ = 31233088012. Its totient is φ = 31231156032.

The previous prime is 31232122007. The next prime is 31232122099. The reversal of 31232122021 is 12022123213.

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 17217113796 + 14015008225 = 131214^2 + 118385^2 .

It is a cyclic number.

It is not a de Polignac number, because 31232122021 - 2¹¹ = 31232119973 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 31232122021.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31232122121) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 432756 + ... + 499741.

It is an arithmetic number, because the mean of its divisors is an integer number (7808272003).

Almost surely, 2^31232122021 is an apocalyptic number.

It is an amenable number.

31232122021 is a deficient number, since it is larger than the sum of its proper divisors (965991).

31232122021 is an equidigital number, since it uses as much as digits as its factorization.

31232122021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 965990.

The product of its (nonzero) digits is 288, while the sum is 19.

Adding to 31232122021 its reverse (12022123213), we get a palindrome (43254245234).

The spelling of 31232122021 in words is "thirty-one billion, two hundred thirty-two million, one hundred twenty-two thousand, twenty-one".