43212321 has 6 divisors (see below), whose sum is σ = 62417810. Its totient is φ = 28808208.

The previous prime is 43212307. The next prime is 43212341. The reversal of 43212321 is 12321234.

43212321 is a `hidden beast` number, since 432 + 1 + 232 + 1 = 666.

43212321 is an esthetic number in base 10, because in such base its adjacent digits differ by 1.

It can be written as a sum of positive squares in only one way, i.e., 27720225 + 15492096 = 5265^2 + 3936^2 .

It is not a de Polignac number, because 43212321 - 2¹³ = 43204129 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 = 43212294 and 43212303.

It is not an unprimeable number, because it can be changed into a prime (43212341) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 2400676 + ... + 2400693.

Almost surely, 2^43212321 is an apocalyptic number.

It is an amenable number.

43212321 is a deficient number, since it is larger than the sum of its proper divisors (19205489).

43212321 is a wasteful number, since it uses less digits than its factorization.

43212321 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4801375 (or 4801372 counting only the distinct ones).

The product of its digits is 288, while the sum is 18.

The square root of 43212321 is about 6573.6079134673. The cubic root of 43212321 is about 350.9154835837.

Adding to 43212321 its reverse (12321234), we get a palindrome (55533555).

The spelling of 43212321 in words is "forty-three million, two hundred twelve thousand, three hundred twenty-one".