31891991041 has 8 divisors (see below), whose sum is σ = 34932404520. Its totient is φ = 28980956928.

The previous prime is 31891991023. The next prime is 31891991063. The reversal of 31891991041 is 14019919813.

It can be written as a sum of positive squares in 4 ways, for example, as 4607558641 + 27284432400 = 67879^2 + 165180^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 31891991041 - 2¹³ = 31891982849 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 31891990982 and 31891991000.

It is not an unprimeable number, because it can be changed into a prime (31891991741) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 32344326 + ... + 32345311.

It is an arithmetic number, because the mean of its divisors is an integer number (4366550565).

Almost surely, 2^31891991041 is an apocalyptic number.

It is an amenable number.

31891991041 is a deficient number, since it is larger than the sum of its proper divisors (3040413479).

31891991041 is a wasteful number, since it uses less digits than its factorization.

31891991041 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 64689683.

The product of its (nonzero) digits is 69984, while the sum is 46.

The spelling of 31891991041 in words is "thirty-one billion, eight hundred ninety-one million, nine hundred ninety-one thousand, forty-one".