43135242221 has 4 divisors (see below), whose sum is σ = 43135875744. Its totient is φ = 43134608700.

The previous prime is 43135242211. The next prime is 43135242223. The reversal of 43135242221 is 12224253134.

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 a de Polignac number, because none of the positive numbers 2^k-43135242221 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (43135242223) 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, 200375 + ... + 355556.

It is an arithmetic number, because the mean of its divisors is an integer number (10783968936).

Almost surely, 2^43135242221 is an apocalyptic number.

It is an amenable number.

43135242221 is a deficient number, since it is larger than the sum of its proper divisors (633523).

43135242221 is an equidigital number, since it uses as much as digits as its factorization.

43135242221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 633522.

The product of its digits is 11520, while the sum is 29.

Adding to 43135242221 its reverse (12224253134), we get a palindrome (55359495355).

The spelling of 43135242221 in words is "forty-three billion, one hundred thirty-five million, two hundred forty-two thousand, two hundred twenty-one".