31444030021 has 4 divisors (see below), whose sum is σ = 31520910700. Its totient is φ = 31367149344.

The previous prime is 31444029989. The next prime is 31444030049. The reversal of 31444030021 is 12003044413.

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 19379424100 + 12064605921 = 139210^2 + 109839^2 .

It is a cyclic number.

It is not a de Polignac number, because 31444030021 - 2⁵ = 31444029989 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 31444029974 and 31444030001.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31444030061) 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, 38439726 + ... + 38440543.

It is an arithmetic number, because the mean of its divisors is an integer number (7880227675).

Almost surely, 2^31444030021 is an apocalyptic number.

It is an amenable number.

31444030021 is a deficient number, since it is larger than the sum of its proper divisors (76880679).

31444030021 is an equidigital number, since it uses as much as digits as its factorization.

31444030021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 76880678.

The product of its (nonzero) digits is 1152, while the sum is 22.

Adding to 31444030021 its reverse (12003044413), we get a palindrome (43447074434).

The spelling of 31444030021 in words is "thirty-one billion, four hundred forty-four million, thirty thousand, twenty-one".