981868817 has 4 divisors (see below), whose sum is σ = 982043316. Its totient is φ = 981694320.

The previous prime is 981868799. The next prime is 981868819. The reversal of 981868817 is 718868189.

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 471063616 + 510805201 = 21704^2 + 22601^2 .

It is a cyclic number.

It is not a de Polignac number, because 981868817 - 2¹⁴ = 981852433 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (981868819) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 78518 + ... + 90159.

It is an arithmetic number, because the mean of its divisors is an integer number (245510829).

Almost surely, 2^981868817 is an apocalyptic number.

It is an amenable number.

981868817 is a deficient number, since it is larger than the sum of its proper divisors (174499).

981868817 is a wasteful number, since it uses less digits than its factorization.

981868817 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 174498.

The product of its digits is 1548288, while the sum is 56.

The square root of 981868817 is about 31334.7860532029. The cubic root of 981868817 is about 993.9193732534.

The spelling of 981868817 in words is "nine hundred eighty-one million, eight hundred sixty-eight thousand, eight hundred seventeen".