43431421 has 4 divisors (see below), whose sum is σ = 47379744. Its totient is φ = 39483100.

The previous prime is 43431389. The next prime is 43431449. The reversal of 43431421 is 12413434.

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 43431421 - 2⁵ = 43431389 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 43431392 and 43431401.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (43431491) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1974145 + ... + 1974166.

It is an arithmetic number, because the mean of its divisors is an integer number (11844936).

Almost surely, 2^43431421 is an apocalyptic number.

It is an amenable number.

43431421 is a deficient number, since it is larger than the sum of its proper divisors (3948323).

43431421 is a wasteful number, since it uses less digits than its factorization.

43431421 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3948322.

The product of its digits is 1152, while the sum is 22.

The square root of 43431421 is about 6590.2519678689. The cubic root of 43431421 is about 351.5075678228.

Adding to 43431421 its reverse (12413434), we get a palindrome (55844855).

The spelling of 43431421 in words is "forty-three million, four hundred thirty-one thousand, four hundred twenty-one".