121806 has 24 divisors (see below), whose sum is σ = 270504. Its totient is φ = 39600.

The previous prime is 121789. The next prime is 121843. The reversal of 121806 is 608121.

121806 = 5² + 6² + ... + 71².

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a Curzon number.

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 121806.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1156 + ... + 1256.

It is an arithmetic number, because the mean of its divisors is an integer number (11271).

2¹²¹⁸⁰⁶ is an apocalyptic number.

121806 is an abundant number, since it is smaller than the sum of its proper divisors (148698).

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

121806 is a wasteful number, since it uses less digits than its factorization.

121806 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 176 (or 173 counting only the distinct ones).

The product of its (nonzero) digits is 96, while the sum is 18.

The square root of 121806 is about 349.0071632503. The cubic root of 121806 is about 49.5704537003.

Adding to 121806 its reverse (608121), we get a palindrome (729927).

The spelling of 121806 in words is "one hundred twenty-one thousand, eight hundred six".