121566 has 8 divisors (see below), whose sum is σ = 243144. Its totient is φ = 40520.

The previous prime is 121559. The next prime is 121571. The reversal of 121566 is 665121.

It is a happy number.

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

121566 is an admirable number.

It is a congruent number.

It is an unprimeable number.

121566 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, 10125 + ... + 10136.

It is an arithmetic number, because the mean of its divisors is an integer number (30393).

2¹²¹⁵⁶⁶ is an apocalyptic number.

121566 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

121566 is a wasteful number, since it uses less digits than its factorization.

121566 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20266.

The product of its digits is 360, while the sum is 21.

The square root of 121566 is about 348.6631612316. The cubic root of 121566 is about 49.5378753075.

Adding to 121566 its reverse (665121), we get a palindrome (786687).

It can be divided in two parts, 121 and 566, that multiplied together give a palindrome (68486).

The spelling of 121566 in words is "one hundred twenty-one thousand, five hundred sixty-six".