698991641 has 4 divisors (see below), whose sum is σ = 701377572. Its totient is φ = 696605712.

The previous prime is 698991593. The next prime is 698991647. The reversal of 698991641 is 146199896.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 468073225 + 230918416 = 21635^2 + 15196^2 .

It is a cyclic number.

It is not a de Polignac number, because 698991641 - 2²⁶ = 631882777 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (698991647) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1192526 + ... + 1193111.

It is an arithmetic number, because the mean of its divisors is an integer number (175344393).

Almost surely, 2^698991641 is an apocalyptic number.

It is an amenable number.

698991641 is a deficient number, since it is larger than the sum of its proper divisors (2385931).

698991641 is a wasteful number, since it uses less digits than its factorization.

698991641 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2385930.

The product of its digits is 839808, while the sum is 53.

The square root of 698991641 is about 26438.4500491235. The cubic root of 698991641 is about 887.4774511496.

The spelling of 698991641 in words is "six hundred ninety-eight million, nine hundred ninety-one thousand, six hundred forty-one".