661238 has 8 divisors (see below), whose sum is σ = 1044120. Its totient is φ = 313200.

The previous prime is 661237. The next prime is 661253. The reversal of 661238 is 832166.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (661231) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 8663 + ... + 8738.

It is an arithmetic number, because the mean of its divisors is an integer number (130515).

2⁶⁶¹²³⁸ is an apocalyptic number.

661238 is a deficient number, since it is larger than the sum of its proper divisors (382882).

661238 is a wasteful number, since it uses less digits than its factorization.

661238 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17422.

The product of its digits is 1728, while the sum is 26.

The square root of 661238 is about 813.1654198255. The cubic root of 661238 is about 87.1202810690.

The spelling of 661238 in words is "six hundred sixty-one thousand, two hundred thirty-eight".