1009817663681 has 4 divisors (see below), whose sum is σ = 1009821722052. Its totient is φ = 1009813605312.

The previous prime is 1009817663641. The next prime is 1009817663753. The reversal of 1009817663681 is 1863667189001.

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 686261471281 + 323556192400 = 828409^2 + 568820^2 .

It is a cyclic number.

It is not a de Polignac number, because 1009817663681 - 2²² = 1009813469377 is a prime.

It is a super-2 number, since 2×1009817663681² (a number of 25 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1009817663611) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1629740 + ... + 2162333.

It is an arithmetic number, because the mean of its divisors is an integer number (252455430513).

Almost surely, 2^{1009817663681} is an apocalyptic number.

It is an amenable number.

1009817663681 is a deficient number, since it is larger than the sum of its proper divisors (4058371).

1009817663681 is an equidigital number, since it uses as much as digits as its factorization.

1009817663681 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4058370.

The product of its (nonzero) digits is 2612736, while the sum is 56.

The spelling of 1009817663681 in words is "one trillion, nine billion, eight hundred seventeen million, six hundred sixty-three thousand, six hundred eighty-one".