43145521 has 8 divisors (see below), whose sum is σ = 45204224. Its totient is φ = 41128560.

The previous prime is 43145497. The next prime is 43145527. The reversal of 43145521 is 12554134.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 43145521 - 2⁷ = 43145393 is a prime.

It is a super-2 number, since 2×43145521² = 3723071964722882, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (43145527) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 8310 + ... + 12463.

It is an arithmetic number, because the mean of its divisors is an integer number (5650528).

Almost surely, 2^43145521 is an apocalyptic number.

It is an amenable number.

43145521 is a deficient number, since it is larger than the sum of its proper divisors (2058703).

43145521 is a wasteful number, since it uses less digits than its factorization.

43145521 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20871.

The product of its digits is 2400, while the sum is 25.

The square root of 43145521 is about 6568.5250246916. The cubic root of 43145521 is about 350.7345687966.

Adding to 43145521 its reverse (12554134), we get a palindrome (55699655).

The spelling of 43145521 in words is "forty-three million, one hundred forty-five thousand, five hundred twenty-one".