1398891 has 8 divisors (see below), whose sum is σ = 2008720. Its totient is φ = 860832.

The previous prime is 1398871. The next prime is 1398911. The reversal of 1398891 is 1988931.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (1398871) and next prime (1398911).

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

It is not a de Polignac number, because 1398891 - 2⁷ = 1398763 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (39), and also a Moran number because the ratio is a prime number: 35869 = 1398891 / (1 + 3 + 9 + 8 + 8 + 9 + 1).

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1398841) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 17896 + ... + 17973.

It is an arithmetic number, because the mean of its divisors is an integer number (251090).

2^1398891 is an apocalyptic number.

1398891 is a deficient number, since it is larger than the sum of its proper divisors (609829).

1398891 is a wasteful number, since it uses less digits than its factorization.

1398891 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 35885.

The product of its digits is 15552, while the sum is 39.

The square root of 1398891 is about 1182.7472257418. The cubic root of 1398891 is about 111.8393476899.

The spelling of 1398891 in words is "one million, three hundred ninety-eight thousand, eight hundred ninety-one".