668550 has 24 divisors (see below), whose sum is σ = 1658376. Its totient is φ = 178240.

The previous prime is 668543. The next prime is 668567. The reversal of 668550 is 55866.

668550 = 27² + 28² + ... + 126².

It is a hoax number, since the sum of its digits (30) coincides with the sum of the digits of its distinct prime factors.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a congruent number.

It is an unprimeable number.

668550 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 2079 + ... + 2378.

It is an arithmetic number, because the mean of its divisors is an integer number (69099).

2⁶⁶⁸⁵⁵⁰ is an apocalyptic number.

668550 is an abundant number, since it is smaller than the sum of its proper divisors (989826).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

668550 is a wasteful number, since it uses less digits than its factorization.

668550 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4472 (or 4467 counting only the distinct ones).

The product of its (nonzero) digits is 7200, while the sum is 30.

The square root of 668550 is about 817.6490689776. The cubic root of 668550 is about 87.4402312919.

The spelling of 668550 in words is "six hundred sixty-eight thousand, five hundred fifty".