43612121 has 4 divisors (see below), whose sum is σ = 49842432. Its totient is φ = 37381812.

The previous prime is 43612111. The next prime is 43612147. The reversal of 43612121 is 12121634.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 43612121 - 2¹⁴ = 43595737 is a prime.

It is an alternating number because its digits alternate between even and odd.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 43612093 and 43612102.

It is not an unprimeable number, because it can be changed into a prime (43612111) 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, 3115145 + ... + 3115158.

It is an arithmetic number, because the mean of its divisors is an integer number (12460608).

Almost surely, 2^43612121 is an apocalyptic number.

It is an amenable number.

43612121 is a deficient number, since it is larger than the sum of its proper divisors (6230311).

43612121 is an equidigital number, since it uses as much as digits as its factorization.

43612121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6230310.

The product of its digits is 288, while the sum is 20.

The square root of 43612121 is about 6603.9473801659. The cubic root of 43612121 is about 351.9943853486.

Adding to 43612121 its reverse (12121634), we get a palindrome (55733755).

The spelling of 43612121 in words is "forty-three million, six hundred twelve thousand, one hundred twenty-one".