660542 has 4 divisors (see below), whose sum is σ = 990816. Its totient is φ = 330270.

The previous prime is 660529. The next prime is 660547. The reversal of 660542 is 245066.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 245066 = 2 ⋅122533.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (660547) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 165134 + ... + 165137.

It is an arithmetic number, because the mean of its divisors is an integer number (247704).

2⁶⁶⁰⁵⁴² is an apocalyptic number.

660542 is a deficient number, since it is larger than the sum of its proper divisors (330274).

660542 is a wasteful number, since it uses less digits than its factorization.

660542 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 330273.

The product of its (nonzero) digits is 1440, while the sum is 23.

The square root of 660542 is about 812.7373499477. The cubic root of 660542 is about 87.0897035752.

The spelling of 660542 in words is "six hundred sixty thousand, five hundred forty-two".