43013561 has 4 divisors (see below), whose sum is σ = 43056000. Its totient is φ = 42971124.

The previous prime is 43013557. The next prime is 43013567. The reversal of 43013561 is 16531034.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 43013561 - 2² = 43013557 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (43013567) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 19661 + ... + 21738.

It is an arithmetic number, because the mean of its divisors is an integer number (10764000).

Almost surely, 2^43013561 is an apocalyptic number.

It is an amenable number.

43013561 is a deficient number, since it is larger than the sum of its proper divisors (42439).

43013561 is a wasteful number, since it uses less digits than its factorization.

43013561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 42438.

The product of its (nonzero) digits is 1080, while the sum is 23.

The square root of 43013561 is about 6558.4724593460. The cubic root of 43013561 is about 350.3766313004.

Adding to 43013561 its reverse (16531034), we get a palindrome (59544595).

The spelling of 43013561 in words is "forty-three million, thirteen thousand, five hundred sixty-one".