1006817981 has 8 divisors (see below), whose sum is σ = 1084537944. Its totient is φ = 929136960.

The previous prime is 1006817963. The next prime is 1006818011. The reversal of 1006817981 is 1897186001.

1006817981 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 4 ways, for example, as 22992025 + 983825956 = 4795^2 + 31366^2 .

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 1006817981 - 2¹⁰ = 1006816957 is a prime.

It is a super-2 number, since 2×1006817981² = 2027364893729832722, which contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1006817081) 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, 65615 + ... + 79491.

It is an arithmetic number, because the mean of its divisors is an integer number (135567243).

Almost surely, 2^1006817981 is an apocalyptic number.

It is an amenable number.

1006817981 is a deficient number, since it is larger than the sum of its proper divisors (77719963).

1006817981 is a wasteful number, since it uses less digits than its factorization.

1006817981 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19471.

The product of its (nonzero) digits is 24192, while the sum is 41.

The square root of 1006817981 is about 31730.3952228774. The cubic root of 1006817981 is about 1002.2675148236.

The spelling of 1006817981 in words is "one billion, six million, eight hundred seventeen thousand, nine hundred eighty-one".