661204 has 12 divisors (see below), whose sum is σ = 1207584. Its totient is φ = 316184.

The previous prime is 661201. The next prime is 661217. The reversal of 661204 is 402166.

It is an Ulam number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (661201) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3502 + ... + 3685.

It is an arithmetic number, because the mean of its divisors is an integer number (100632).

2⁶⁶¹²⁰⁴ is an apocalyptic number.

It is an amenable number.

661204 is a deficient number, since it is larger than the sum of its proper divisors (546380).

661204 is a wasteful number, since it uses less digits than its factorization.

661204 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7214 (or 7212 counting only the distinct ones).

The product of its (nonzero) digits is 288, while the sum is 19.

The square root of 661204 is about 813.1445136014. The cubic root of 661204 is about 87.1187878394.

The spelling of 661204 in words is "six hundred sixty-one thousand, two hundred four".