667790 has 16 divisors (see below), whose sum is σ = 1230768. Its totient is φ = 260736.

The previous prime is 667781. The next prime is 667801. The reversal of 667790 is 97766.

667790 = 103² + 104² + ... + 145².

It is a self number, because there is not a number n which added to its sum of digits gives 667790.

It is a congruent number.

It is an unprimeable number.

667790 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 7 ways as a sum of consecutive naturals, for example, 347 + ... + 1206.

It is an arithmetic number, because the mean of its divisors is an integer number (76923).

2⁶⁶⁷⁷⁹⁰ is an apocalyptic number.

667790 is a deficient number, since it is larger than the sum of its proper divisors (562978).

667790 is a wasteful number, since it uses less digits than its factorization.

667790 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1603.

The product of its (nonzero) digits is 15876, while the sum is 35.

The square root of 667790 is about 817.1841897638. The cubic root of 667790 is about 87.4070850434.

The spelling of 667790 in words is "six hundred sixty-seven thousand, seven hundred ninety".