43978513 has 2 divisors, whose sum is σ = 43978514. Its totient is φ = 43978512.

The previous prime is 43978457. The next prime is 43978567. The reversal of 43978513 is 31587934.

43978513 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 27793984 + 16184529 = 5272^2 + 4023^2 .

It is a cyclic number.

It is not a de Polignac number, because 43978513 - 2²¹ = 41881361 is a prime.

It is not a weakly prime, because it can be changed into another prime (43978573) 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, 21989256 + 21989257.

It is an arithmetic number, because the mean of its divisors is an integer number (21989257).

Almost surely, 2^43978513 is an apocalyptic number.

It is an amenable number.

43978513 is a deficient number, since it is larger than the sum of its proper divisors (1).

43978513 is an equidigital number, since it uses as much as digits as its factorization.

43978513 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 90720, while the sum is 40.

The square root of 43978513 is about 6631.6297393627. The cubic root of 43978513 is about 352.9773570584.

The spelling of 43978513 in words is "forty-three million, nine hundred seventy-eight thousand, five hundred thirteen".