31101030221 has 4 divisors (see below), whose sum is σ = 31105292700. Its totient is φ = 31096767744.

The previous prime is 31101030199. The next prime is 31101030281. The reversal of 31101030221 is 12203010113.

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 19884102121 + 11216928100 = 141011^2 + 105910^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-31101030221 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 31101030196 and 31101030205.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31101030281) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2120276 + ... + 2134893.

It is an arithmetic number, because the mean of its divisors is an integer number (7776323175).

Almost surely, 2^31101030221 is an apocalyptic number.

It is an amenable number.

31101030221 is a deficient number, since it is larger than the sum of its proper divisors (4262479).

31101030221 is an equidigital number, since it uses as much as digits as its factorization.

31101030221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4262478.

The product of its (nonzero) digits is 36, while the sum is 14.

Adding to 31101030221 its reverse (12203010113), we get a palindrome (43304040334).

The spelling of 31101030221 in words is "thirty-one billion, one hundred one million, thirty thousand, two hundred twenty-one".