698921 has 4 divisors (see below), whose sum is σ = 740052. Its totient is φ = 657792.

The previous prime is 698903. The next prime is 698923. The reversal of 698921 is 129896.

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 547600 + 151321 = 740^2 + 389^2 .

It is a cyclic number.

It is not a de Polignac number, because 698921 - 2¹⁰ = 697897 is a prime.

It is an Ulam number.

It is an alternating number because its digits alternate between even and odd.

It is a Duffinian number.

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 698921.

It is not an unprimeable number, because it can be changed into a prime (698923) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 20540 + ... + 20573.

It is an arithmetic number, because the mean of its divisors is an integer number (185013).

2⁶⁹⁸⁹²¹ is an apocalyptic number.

It is an amenable number.

698921 is a deficient number, since it is larger than the sum of its proper divisors (41131).

698921 is a wasteful number, since it uses less digits than its factorization.

698921 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 41130.

The product of its digits is 7776, while the sum is 35.

The square root of 698921 is about 836.0149520194. The cubic root of 698921 is about 88.7447553602.

The spelling of 698921 in words is "six hundred ninety-eight thousand, nine hundred twenty-one".