665542 has 8 divisors (see below), whose sum is σ = 1009800. Its totient is φ = 328944.

The previous prime is 665527. The next prime is 665549. The reversal of 665542 is 245566.

665542 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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

It is a plaindrome in base 14.

It is a nialpdrome in base 10.

It is a self number, because there is not a number n which added to its sum of digits gives 665542.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (665549) by changing a digit.

665542 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1692 + ... + 2047.

It is an arithmetic number, because the mean of its divisors is an integer number (126225).

2⁶⁶⁵⁵⁴² is an apocalyptic number.

665542 is a deficient number, since it is larger than the sum of its proper divisors (344258).

665542 is a wasteful number, since it uses less digits than its factorization.

665542 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3830.

The product of its digits is 7200, while the sum is 28.

The square root of 665542 is about 815.8075753510. The cubic root of 665542 is about 87.3088944820.

The spelling of 665542 in words is "six hundred sixty-five thousand, five hundred forty-two".