1031881581 has 6 divisors (see below), whose sum is σ = 1490495630. Its totient is φ = 687921048.

The previous prime is 1031881561. The next prime is 1031881639. The reversal of 1031881581 is 1851881301.

It is a happy number.

1031881581 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in only one way, i.e., 1024640100 + 7241481 = 32010^2 + 2691^2 .

It is not a de Polignac number, because 1031881581 - 2⁹ = 1031881069 is a prime.

It is a super-2 number, since 2×1031881581² = 2129559194414119122, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1031881561) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 57326746 + ... + 57326763.

Almost surely, 2^1031881581 is an apocalyptic number.

It is an amenable number.

1031881581 is a deficient number, since it is larger than the sum of its proper divisors (458614049).

1031881581 is a wasteful number, since it uses less digits than its factorization.

1031881581 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 114653515 (or 114653512 counting only the distinct ones).

The product of its (nonzero) digits is 7680, while the sum is 36.

The square root of 1031881581 is about 32122.9136443132. The cubic root of 1031881581 is about 1010.5162152187.

The spelling of 1031881581 in words is "one billion, thirty-one million, eight hundred eighty-one thousand, five hundred eighty-one".