988660781 has 8 divisors (see below), whose sum is σ = 1007927064. Its totient is φ = 969417280.

The previous prime is 988660759. The next prime is 988660787. The reversal of 988660781 is 187066889.

It can be written as a sum of positive squares in 4 ways, for example, as 8031556 + 980629225 = 2834^2 + 31315^2 .

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 988660781 - 2²² = 984466477 is a prime.

It is a super-2 number, since 2×988660781² = 1954900279775059922, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (53).

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (988660787) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 101171 + ... + 110511.

It is an arithmetic number, because the mean of its divisors is an integer number (125990883).

Almost surely, 2^988660781 is an apocalyptic number.

It is an amenable number.

988660781 is a deficient number, since it is larger than the sum of its proper divisors (19266283).

988660781 is a wasteful number, since it uses less digits than its factorization.

988660781 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11391.

The product of its (nonzero) digits is 1161216, while the sum is 53.

The square root of 988660781 is about 31442.9766561628. The cubic root of 988660781 is about 996.2058832170.

The spelling of 988660781 in words is "nine hundred eighty-eight million, six hundred sixty thousand, seven hundred eighty-one".