670 can be written using four 4's:
See also 113
670 has 8
divisors (see below), whose sum is σ = 1224
Its totient is φ = 264
The previous prime is 661. The next prime is 673. The reversal of 670 is 76.
670 = T4 + T5 + ... +
It is a sphenic number, since it is the product of 3 distinct primes.
It is an alternating number because its digits alternate between even and odd.
It is a plaindrome in base 8, base 11, base 12, base 14 and base 16.
It is a self number, because there is not a number n which added to its sum of digits gives 670.
It is a congruent number.
It is not an unprimeable number, because it can be changed into a prime (673) by changing a digit.
670 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 3 ways as a sum of consecutive naturals, for example, 24 + ... + 43.
It is an arithmetic number, because the mean of its divisors is an integer number (153).
670 is a deficient number, since it is larger than the sum of its proper divisors (554).
670 is a wasteful number, since it uses less digits than its factorization.
670 is an evil number, because the sum of its binary digits is even.
The sum of its prime factors is 74.
The product of its (nonzero) digits is 42, while the sum is 13.
The square root of 670 is about 25.8843582111.
The cubic root of 670 is about 8.7503401228.
The spelling of 670 in words is "six hundred seventy", and thus it is an aban number and an oban number.