4123121421 has 16 divisors (see below), whose sum is σ = 5544658944. Its totient is φ = 2725196544.

The previous prime is 4123121411. The next prime is 4123121461. The reversal of 4123121421 is 1241213214.

It is not a de Polignac number, because 4123121421 - 2⁶ = 4123121357 is a prime.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (4123121411) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 726025 + ... + 731681.

It is an arithmetic number, because the mean of its divisors is an integer number (346541184).

Almost surely, 2^4123121421 is an apocalyptic number.

It is an amenable number.

4123121421 is a deficient number, since it is larger than the sum of its proper divisors (1421537523).

4123121421 is a wasteful number, since it uses less digits than its factorization.

4123121421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7700.

The product of its digits is 384, while the sum is 21.

The square root of 4123121421 is about 64211.5365101942. The cubic root of 4123121421 is about 1603.5236691765.

Adding to 4123121421 its reverse (1241213214), we get a palindrome (5364334635).

The spelling of 4123121421 in words is "four billion, one hundred twenty-three million, one hundred twenty-one thousand, four hundred twenty-one".