1931071081 has 4 divisors (see below), whose sum is σ = 1941740164. Its totient is φ = 1920402000.

The previous prime is 1931071073. The next prime is 1931071139. The reversal of 1931071081 is 1801701391.

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 684345600 + 1246725481 = 26160^2 + 35309^2 .

It is a cyclic number.

It is not a de Polignac number, because 1931071081 - 2³ = 1931071073 is a prime.

It is a super-2 number, since 2×1931071081² = 7458071039749017122, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1931071001) 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, 5334270 + ... + 5334631.

It is an arithmetic number, because the mean of its divisors is an integer number (485435041).

Almost surely, 2^1931071081 is an apocalyptic number.

It is an amenable number.

1931071081 is a deficient number, since it is larger than the sum of its proper divisors (10669083).

1931071081 is a wasteful number, since it uses less digits than its factorization.

1931071081 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10669082.

The product of its (nonzero) digits is 1512, while the sum is 31.

The square root of 1931071081 is about 43943.9538617089. The cubic root of 1931071081 is about 1245.2773436309.

The spelling of 1931071081 in words is "one billion, nine hundred thirty-one million, seventy-one thousand, eighty-one".