391898 has 8 divisors (see below), whose sum is σ = 633108. Its totient is φ = 180864.

The previous prime is 391891. The next prime is 391903. The reversal of 391898 is 898193.

It can be written as a sum of positive squares in 2 ways, for example, as 375769 + 16129 = 613^2 + 127^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is not an unprimeable number, because it can be changed into a prime (391891) 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, 7511 + ... + 7562.

2³⁹¹⁸⁹⁸ is an apocalyptic number.

391898 is a deficient number, since it is larger than the sum of its proper divisors (241210).

391898 is a wasteful number, since it uses less digits than its factorization.

391898 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15088.

The product of its digits is 15552, while the sum is 38.

The square root of 391898 is about 626.0175716384. The cubic root of 391898 is about 73.1797658746.

The spelling of 391898 in words is "three hundred ninety-one thousand, eight hundred ninety-eight".