43123421 has 4 divisors (see below), whose sum is σ = 47043744. Its totient is φ = 39203100.

The previous prime is 43123403. The next prime is 43123429. The reversal of 43123421 is 12432134.

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 43123421 - 2²² = 38929117 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 43123393 and 43123402.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (43123429) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1960145 + ... + 1960166.

It is an arithmetic number, because the mean of its divisors is an integer number (11760936).

Almost surely, 2^43123421 is an apocalyptic number.

It is an amenable number.

43123421 is a deficient number, since it is larger than the sum of its proper divisors (3920323).

43123421 is a wasteful number, since it uses less digits than its factorization.

43123421 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3920322.

The product of its digits is 576, while the sum is 20.

The square root of 43123421 is about 6566.8425441760. The cubic root of 43123421 is about 350.6746741454.

Adding to 43123421 its reverse (12432134), we get a palindrome (55555555).

The spelling of 43123421 in words is "forty-three million, one hundred twenty-three thousand, four hundred twenty-one".