31000030321 has 4 divisors (see below), whose sum is σ = 33384648052. Its totient is φ = 28615412592.

The previous prime is 31000030319. The next prime is 31000030331. The reversal of 31000030321 is 12303000013.

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 3568389696 + 27431640625 = 59736^2 + 165625^2 .

It is not a de Polignac number, because 31000030321 - 2¹ = 31000030319 is a prime.

It is a super-2 number, since 2×31000030321² (a number of 22 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (13), and also a Moran number because the ratio is a prime number: 2384617717 = 31000030321 / (3 + 1 + 0 + 0 + 0 + 0 + 3 + 0 + 3 + 2 + 1).

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (31000030331) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1192308846 + ... + 1192308871.

It is an arithmetic number, because the mean of its divisors is an integer number (8346162013).

Almost surely, 2^31000030321 is an apocalyptic number.

It is an amenable number.

31000030321 is a deficient number, since it is larger than the sum of its proper divisors (2384617731).

31000030321 is a wasteful number, since it uses less digits than its factorization.

31000030321 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2384617730.

The product of its (nonzero) digits is 54, while the sum is 13.

Adding to 31000030321 its reverse (12303000013), we get a palindrome (43303030334).

The spelling of 31000030321 in words is "thirty-one billion, thirty thousand, three hundred twenty-one".