1071309871681 has 9 divisors (see below), whose sum is σ = 1246226034081. Its totient is φ = 918259394052.

The previous prime is 1071309871673. The next prime is 1071309871721. The reversal of 1071309871681 is 1861789031701.

It is a happy number.

The square root of 1071309871681 is 1035041.

It is a perfect power (a square), and thus also a powerful number.

It is not a de Polignac number, because 1071309871681 - 2³ = 1071309871673 is a prime.

It is a super-2 number, since 2×1071309871681² (a number of 25 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (1071309871661) by changing a digit.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 7171356 + ... + 7319218.

Almost surely, 2^{1071309871681} is an apocalyptic number.

1071309871681 is the 1035041-st square number.

1071309871681 is the 517521-st centered octagonal number.

It is an amenable number.

1071309871681 is a deficient number, since it is larger than the sum of its proper divisors (174916162400).

1071309871681 is an frugal number, since it uses more digits than its factorization.

1071309871681 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 295740 (or 147870 counting only the distinct ones).

The product of its (nonzero) digits is 508032, while the sum is 52.

The spelling of 1071309871681 in words is "one trillion, seventy-one billion, three hundred nine million, eight hundred seventy-one thousand, six hundred eighty-one".