43987213 has 2 divisors, whose sum is σ = 43987214. Its totient is φ = 43987212.

The previous prime is 43987199. The next prime is 43987231. The reversal of 43987213 is 31278934.

43987213 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

Together with next prime (43987231) it forms an Ormiston pair, because they use the same digits, order apart.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 43059844 + 927369 = 6562^2 + 963^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-43987213 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (43987243) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 21993606 + 21993607.

It is an arithmetic number, because the mean of its divisors is an integer number (21993607).

Almost surely, 2^43987213 is an apocalyptic number.

It is an amenable number.

43987213 is a deficient number, since it is larger than the sum of its proper divisors (1).

43987213 is an equidigital number, since it uses as much as digits as its factorization.

43987213 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 36288, while the sum is 37.

The square root of 43987213 is about 6632.2856542824. The cubic root of 43987213 is about 353.0006313069. Note that the first 3 decimals are identical.

It can be divided in two parts, 4398 and 7213, that added together give a palindrome (11611).

The spelling of 43987213 in words is "forty-three million, nine hundred eighty-seven thousand, two hundred thirteen".