43854021 has 8 divisors (see below), whose sum is σ = 64968960. Its totient is φ = 29235996.

The previous prime is 43854011. The next prime is 43854037. The reversal of 43854021 is 12045834.

It is not a de Polignac number, because 43854021 - 2¹⁰ = 43852997 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27), and also a Moran number because the ratio is a prime number: 1624223 = 43854021 / (4 + 3 + 8 + 5 + 4 + 0 + 2 + 1).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (43854011) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 812085 + ... + 812138.

It is an arithmetic number, because the mean of its divisors is an integer number (8121120).

Almost surely, 2^43854021 is an apocalyptic number.

It is an amenable number.

43854021 is a deficient number, since it is larger than the sum of its proper divisors (21114939).

43854021 is a wasteful number, since it uses less digits than its factorization.

43854021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1624232 (or 1624226 counting only the distinct ones).

The product of its (nonzero) digits is 3840, while the sum is 27.

The square root of 43854021 is about 6622.2368577392. The cubic root of 43854021 is about 352.6439792097.

Adding to 43854021 its reverse (12045834), we get a palindrome (55899855).

The spelling of 43854021 in words is "forty-three million, eight hundred fifty-four thousand, twenty-one".