669900 has 144 divisors (see below), whose sum is σ = 2499840.
Its totient is φ = 134400.
The previous prime is 669887. The next prime is 669901. The reversal of 669900 is 9966.
669900 = T5 + T6 + ... +
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 zygodrome in base 10.
It is not an unprimeable number, because it can be changed into a prime (669901) by changing a digit.
669900 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 47 ways as a sum of consecutive naturals, for example, 23086 + ... + 23114.
It is an arithmetic number, because the mean of its divisors is an integer number (17360).
2669900 is an apocalyptic number.
669900 is a gapful number since it is divisible by the number (60) formed by its first and last digit.
It is an amenable number.
It is a practical number, because each smaller number is the sum of distinct divisors of 669900, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1249920).
669900 is an abundant number, since it is smaller than the sum of its proper divisors (1829940).
It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.
669900 is a wasteful number, since it uses less digits than its factorization.
669900 is an odious number, because the sum of its binary digits is odd.
The sum of its prime factors is 64 (or 57 counting only the distinct ones).
The product of its (nonzero) digits is 2916, while the sum is 30.
The square root of 669900 is about 818.4741901856.
The cubic root of 669900 is about 87.4990476087.
The spelling of 669900 in words is "six hundred sixty-nine thousand, nine hundred".