121663 has 4 divisors (see below), whose sum is σ = 123120. Its totient is φ = 120208.

The previous prime is 121661. The next prime is 121687. The reversal of 121663 is 366121.

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

It is a cyclic number.

It is not a de Polignac number, because 121663 - 2¹ = 121661 is a prime.

It is an Ulam number.

It is a Duffinian number.

121663 is a lucky number.

It is a self number, because there is not a number n which added to its sum of digits gives 121663.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (121661) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 595 + ... + 772.

It is an arithmetic number, because the mean of its divisors is an integer number (30780).

2¹²¹⁶⁶³ is an apocalyptic number.

121663 is a deficient number, since it is larger than the sum of its proper divisors (1457).

121663 is an equidigital number, since it uses as much as digits as its factorization.

121663 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1456.

The product of its digits is 216, while the sum is 19.

The square root of 121663 is about 348.8022362314. The cubic root of 121663 is about 49.5510475663.

Adding to 121663 its reverse (366121), we get a palindrome (487784).

It can be divided in two parts, 121 and 663, that added together give a square (784 = 28²).

The spelling of 121663 in words is "one hundred twenty-one thousand, six hundred sixty-three".