40121 has 4 divisors (see below), whose sum is σ = 40932. Its totient is φ = 39312.

The previous prime is 40111. The next prime is 40123. The reversal of 40121 is 12104.

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

It can be written as a sum of positive squares in 2 ways, for example, as 26896 + 13225 = 164^2 + 115^2 .

It is a cyclic number.

It is not a de Polignac number, because 40121 - 2¹⁰ = 39097 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 40099 and 40108.

It is not an unprimeable number, because it can be changed into a prime (40123) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 326 + ... + 431.

It is an arithmetic number, because the mean of its divisors is an integer number (10233).

2⁴⁰¹²¹ is an apocalyptic number.

It is an amenable number.

40121 is a deficient number, since it is larger than the sum of its proper divisors (811).

40121 is an equidigital number, since it uses as much as digits as its factorization.

40121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 810.

The product of its (nonzero) digits is 8, while the sum is 8.

The square root of 40121 is about 200.3022715797. The cubic root of 40121 is about 34.2339687349.

Adding to 40121 its reverse (12104), we get a palindrome (52225).

It can be divided in two parts, 40 and 121, that added together give a palindrome (161).

The spelling of 40121 in words is "forty thousand, one hundred twenty-one", and thus it is an iban number.