660398 has 4 divisors (see below), whose sum is σ = 990600. Its totient is φ = 330198.

The previous prime is 660391. The next prime is 660403. The reversal of 660398 is 893066.

It is a happy number.

660398 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 893066 = 2 ⋅446533.

It is a super-2 number, since 2×660398² = 872251036808, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (660391) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 165098 + ... + 165101.

It is an arithmetic number, because the mean of its divisors is an integer number (247650).

2⁶⁶⁰³⁹⁸ is an apocalyptic number.

660398 is a deficient number, since it is larger than the sum of its proper divisors (330202).

660398 is a wasteful number, since it uses less digits than its factorization.

660398 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 330201.

The product of its (nonzero) digits is 7776, while the sum is 32.

The square root of 660398 is about 812.6487556134. The cubic root of 660398 is about 87.0833745157.

The spelling of 660398 in words is "six hundred sixty thousand, three hundred ninety-eight".