987898661 has 2 divisors, whose sum is σ = 987898662. Its totient is φ = 987898660.

The previous prime is 987898633. The next prime is 987898663. The reversal of 987898661 is 166898789.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 852990436 + 134908225 = 29206^2 + 11615^2 .

It is a cyclic number.

It is not a de Polignac number, because 987898661 - 2²² = 983704357 is a prime.

It is a Sophie Germain prime.

Together with 987898663, it forms a pair of twin primes.

It is a Chen prime.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 987898594 and 987898603.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (987898663) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 493949330 + 493949331.

It is an arithmetic number, because the mean of its divisors is an integer number (493949331).

Almost surely, 2^987898661 is an apocalyptic number.

It is an amenable number.

987898661 is a deficient number, since it is larger than the sum of its proper divisors (1).

987898661 is an equidigital number, since it uses as much as digits as its factorization.

987898661 is an evil number, because the sum of its binary digits is even.

The product of its digits is 10450944, while the sum is 62.

The square root of 987898661 is about 31430.8552381255. The cubic root of 987898661 is about 995.9498386726.

The spelling of 987898661 in words is "nine hundred eighty-seven million, eight hundred ninety-eight thousand, six hundred sixty-one".