31000431005 has 16 divisors (see below), whose sum is σ = 39437558640. Its totient is φ = 23312596992.

The previous prime is 31000430999. The next prime is 31000431013. The reversal of 31000431005 is 50013400013.

It can be written as a sum of positive squares in 8 ways, for example, as 11345232196 + 19655198809 = 106514^2 + 140197^2 .

It is a cyclic number.

It is not a de Polignac number, because 31000431005 - 2¹⁸ = 31000168861 is a prime.

It is a super-2 number, since 2×31000431005² (a number of 22 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (17).

It is a congruent number.

It is an unprimeable number.

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 15 ways as a sum of consecutive naturals, for example, 156644 + ... + 294173.

It is an arithmetic number, because the mean of its divisors is an integer number (2464847415).

Almost surely, 2^31000431005 is an apocalyptic number.

It is an amenable number.

31000431005 is a deficient number, since it is larger than the sum of its proper divisors (8437127635).

31000431005 is a wasteful number, since it uses less digits than its factorization.

31000431005 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 451648.

The product of its (nonzero) digits is 180, while the sum is 17.

Adding to 31000431005 its reverse (50013400013), we get a palindrome (81013831018).

The spelling of 31000431005 in words is "thirty-one billion, four hundred thirty-one thousand, five".