698137681 has 2 divisors, whose sum is σ = 698137682. Its totient is φ = 698137680.

The previous prime is 698137663. The next prime is 698137721. The reversal of 698137681 is 186731896.

698137681 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 536339281 + 161798400 = 23159^2 + 12720^2 .

It is a cyclic number.

It is not a de Polignac number, because 698137681 - 2⁹ = 698137169 is a prime.

It is a super-2 number, since 2×698137681² = 974792443264115522, which contains 22 as substring.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (698132681) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 349068840 + 349068841.

It is an arithmetic number, because the mean of its divisors is an integer number (349068841).

Almost surely, 2^698137681 is an apocalyptic number.

It is an amenable number.

698137681 is a deficient number, since it is larger than the sum of its proper divisors (1).

698137681 is an equidigital number, since it uses as much as digits as its factorization.

698137681 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 435456, while the sum is 49.

The square root of 698137681 is about 26422.2951501190. The cubic root of 698137681 is about 887.1158926607.

The spelling of 698137681 in words is "six hundred ninety-eight million, one hundred thirty-seven thousand, six hundred eighty-one".