661442 has 4 divisors (see below), whose sum is σ = 992166. Its totient is φ = 330720.

The previous prime is 661439. The next prime is 661459. The reversal of 661442 is 244166.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 657721 + 3721 = 811^2 + 61^2 .

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 165359 + ... + 165362.

2⁶⁶¹⁴⁴² is an apocalyptic number.

661442 is a deficient number, since it is larger than the sum of its proper divisors (330724).

661442 is a wasteful number, since it uses less digits than its factorization.

661442 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 330723.

The product of its digits is 1152, while the sum is 23.

The square root of 661442 is about 813.2908458848. The cubic root of 661442 is about 87.1292393714.

The spelling of 661442 in words is "six hundred sixty-one thousand, four hundred forty-two".