998768681 has 2 divisors, whose sum is σ = 998768682. Its totient is φ = 998768680.

The previous prime is 998768599. The next prime is 998768689. The reversal of 998768681 is 186867899.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 869719081 + 129049600 = 29491^2 + 11360^2 .

It is a cyclic number.

It is not a de Polignac number, because 998768681 - 2¹⁴ = 998752297 is a prime.

It is a super-2 number, since 2×998768681² = 1995077756292959522, which contains 22 as substring.

It is a Sophie Germain prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (998768689) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 499384340 + 499384341.

It is an arithmetic number, because the mean of its divisors is an integer number (499384341).

Almost surely, 2^998768681 is an apocalyptic number.

It is an amenable number.

998768681 is a deficient number, since it is larger than the sum of its proper divisors (1).

998768681 is an equidigital number, since it uses as much as digits as its factorization.

998768681 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 998768681 is about 31603.3017420649. The cubic root of 998768681 is about 999.5893917573.

The spelling of 998768681 in words is "nine hundred ninety-eight million, seven hundred sixty-eight thousand, six hundred eighty-one".