43878643 has 2 divisors, whose sum is σ = 43878644. Its totient is φ = 43878642.

The previous prime is 43878631. The next prime is 43878661. The reversal of 43878643 is 34687834.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 43878643 - 2²¹ = 41781491 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 43878643.

It is not a weakly prime, because it can be changed into another prime (43878613) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 21939321 + 21939322.

It is an arithmetic number, because the mean of its divisors is an integer number (21939322).

Almost surely, 2^43878643 is an apocalyptic number.

43878643 is a deficient number, since it is larger than the sum of its proper divisors (1).

43878643 is an equidigital number, since it uses as much as digits as its factorization.

43878643 is an evil number, because the sum of its binary digits is even.

The product of its digits is 387072, while the sum is 43.

The square root of 43878643 is about 6624.0956363869. The cubic root of 43878643 is about 352.7099646113.

It can be divided in two parts, 43878 and 643, that added together give a square (44521 = 211²).

The spelling of 43878643 in words is "forty-three million, eight hundred seventy-eight thousand, six hundred forty-three".