43845561 has 12 divisors (see below), whose sum is σ = 63405888. Its totient is φ = 29196504.

The previous prime is 43845541. The next prime is 43845587. The reversal of 43845561 is 16554834.

It is a happy number.

It is not a de Polignac number, because 43845561 - 2¹³ = 43837369 is a prime.

It is a Smith number, since the sum of its digits (36) coincides with the sum of the digits of its prime factors.

It is not an unprimeable number, because it can be changed into a prime (43845511) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 7276 + ... + 11858.

It is an arithmetic number, because the mean of its divisors is an integer number (5283824).

Almost surely, 2^43845561 is an apocalyptic number.

It is an amenable number.

43845561 is a deficient number, since it is larger than the sum of its proper divisors (19560327).

43845561 is a wasteful number, since it uses less digits than its factorization.

43845561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5652 (or 5649 counting only the distinct ones).

The product of its digits is 57600, while the sum is 36.

The square root of 43845561 is about 6621.5980699526. The cubic root of 43845561 is about 352.6213012442.

It can be divided in two parts, 438455 and 61, that added together give a triangular number (438516 = T₉₃₆).

The spelling of 43845561 in words is "forty-three million, eight hundred forty-five thousand, five hundred sixty-one".