661946 has 8 divisors (see below), whose sum is σ = 1051380. Its totient is φ = 311488.

The previous prime is 661939. The next prime is 661949. The reversal of 661946 is 649166.

661946 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 2 ways, for example, as 657721 + 4225 = 811^2 + 65^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a Curzon number.

It is a plaindrome in base 14.

It is not an unprimeable number, because it can be changed into a prime (661949) 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, 9701 + ... + 9768.

2⁶⁶¹⁹⁴⁶ is an apocalyptic number.

661946 is a deficient number, since it is larger than the sum of its proper divisors (389434).

661946 is a wasteful number, since it uses less digits than its factorization.

661946 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19488.

The product of its digits is 7776, while the sum is 32.

The square root of 661946 is about 813.6006391345. The cubic root of 661946 is about 87.1513637541.

The spelling of 661946 in words is "six hundred sixty-one thousand, nine hundred forty-six".