986400661 has 2 divisors, whose sum is σ = 986400662. Its totient is φ = 986400660.

The previous prime is 986400659. The next prime is 986400671. The reversal of 986400661 is 166004689.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 646735761 + 339664900 = 25431^2 + 18430^2 .

It is an emirp because it is prime and its reverse (166004689) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 986400661 - 2¹ = 986400659 is a prime.

Together with 986400659, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (986400671) 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 as a sum of consecutive naturals, namely, 493200330 + 493200331.

It is an arithmetic number, because the mean of its divisors is an integer number (493200331).

Almost surely, 2^986400661 is an apocalyptic number.

It is an amenable number.

986400661 is a deficient number, since it is larger than the sum of its proper divisors (1).

986400661 is an equidigital number, since it uses as much as digits as its factorization.

986400661 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 62208, while the sum is 40.

The square root of 986400661 is about 31407.0161110539. The cubic root of 986400661 is about 995.4461812124.

The spelling of 986400661 in words is "nine hundred eighty-six million, four hundred thousand, six hundred sixty-one".