669998 has 8 divisors (see below), whose sum is σ = 1148592. Its totient is φ = 287136.

The previous prime is 669989. The next prime is 670001. The reversal of 669998 is 899966.

It is a happy number.

669998 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 23915 + ... + 23942.

It is an arithmetic number, because the mean of its divisors is an integer number (143574).

2⁶⁶⁹⁹⁹⁸ is an apocalyptic number.

669998 is a deficient number, since it is larger than the sum of its proper divisors (478594).

669998 is a wasteful number, since it uses less digits than its factorization.

669998 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 47866.

The product of its digits is 209952, while the sum is 47.

The square root of 669998 is about 818.5340554919. The cubic root of 669998 is about 87.5033141602.

The spelling of 669998 in words is "six hundred sixty-nine thousand, nine hundred ninety-eight".