4000121 has 4 divisors (see below), whose sum is σ = 4009332. Its totient is φ = 3990912.

The previous prime is 4000093. The next prime is 4000133. The reversal of 4000121 is 1210004.

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 3474496 + 525625 = 1864^2 + 725^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-4000121 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 4000099 and 4000108.

It is not an unprimeable number, because it can be changed into a prime (4003121) 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, 3920 + ... + 4833.

It is an arithmetic number, because the mean of its divisors is an integer number (1002333).

Almost surely, 2^4000121 is an apocalyptic number.

It is an amenable number.

4000121 is a deficient number, since it is larger than the sum of its proper divisors (9211).

4000121 is an equidigital number, since it uses as much as digits as its factorization.

4000121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9210.

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

The square root of 4000121 is about 2000.0302497712. The cubic root of 4000121 is about 158.7417058101.

Adding to 4000121 its reverse (1210004), we get a palindrome (5210125).

The spelling of 4000121 in words is "four million, one hundred twenty-one", and thus it is an aban number.