43242111221 has 2 divisors, whose sum is σ = 43242111222. Its totient is φ = 43242111220.

The previous prime is 43242111197. The next prime is 43242111247. The reversal of 43242111221 is 12211124234.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 24194247025 + 19047864196 = 155545^2 + 138014^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-43242111221 is a prime.

It is a super-2 number, since 2×43242111221² (a number of 22 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (43242111271) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 21621055610 + 21621055611.

It is an arithmetic number, because the mean of its divisors is an integer number (21621055611).

Almost surely, 2^43242111221 is an apocalyptic number.

It is an amenable number.

43242111221 is a deficient number, since it is larger than the sum of its proper divisors (1).

43242111221 is an equidigital number, since it uses as much as digits as its factorization.

43242111221 is an evil number, because the sum of its binary digits is even.

The product of its digits is 768, while the sum is 23.

Adding to 43242111221 its reverse (12211124234), we get a palindrome (55453235455).

The spelling of 43242111221 in words is "forty-three billion, two hundred forty-two million, one hundred eleven thousand, two hundred twenty-one".