698479981 has 2 divisors, whose sum is σ = 698479982. Its totient is φ = 698479980.

The previous prime is 698479979. The next prime is 698480009. The reversal of 698479981 is 189974896.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 585398025 + 113081956 = 24195^2 + 10634^2 .

It is a cyclic number.

It is not a de Polignac number, because 698479981 - 2¹ = 698479979 is a prime.

It is a super-2 number, since 2×698479981² = 975748567715520722, which contains 22 as substring.

Together with 698479979, 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 (698479961) 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, 349239990 + 349239991.

It is an arithmetic number, because the mean of its divisors is an integer number (349239991).

Almost surely, 2^698479981 is an apocalyptic number.

It is an amenable number.

698479981 is a deficient number, since it is larger than the sum of its proper divisors (1).

698479981 is an equidigital number, since it uses as much as digits as its factorization.

698479981 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 7838208, while the sum is 61.

The square root of 698479981 is about 26428.7718405529. The cubic root of 698479981 is about 887.2608545898.

The spelling of 698479981 in words is "six hundred ninety-eight million, four hundred seventy-nine thousand, nine hundred eighty-one".