43218761 has 2 divisors, whose sum is σ = 43218762. Its totient is φ = 43218760.

The previous prime is 43218719. The next prime is 43218779. The reversal of 43218761 is 16781234.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 35760400 + 7458361 = 5980^2 + 2731^2 .

It is a cyclic number.

It is not a de Polignac number, because 43218761 - 2²² = 39024457 is a prime.

It is a super-2 number, since 2×43218761² = 3735722604750242, which contains 22 as substring.

It is a Chen prime.

It is an alternating number because its digits alternate between even and odd.

It is not a weakly prime, because it can be changed into another prime (43218361) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 21609380 + 21609381.

It is an arithmetic number, because the mean of its divisors is an integer number (21609381).

Almost surely, 2^43218761 is an apocalyptic number.

It is an amenable number.

43218761 is a deficient number, since it is larger than the sum of its proper divisors (1).

43218761 is an equidigital number, since it uses as much as digits as its factorization.

43218761 is an evil number, because the sum of its binary digits is even.

The product of its digits is 8064, while the sum is 32.

The square root of 43218761 is about 6574.0977327691. The cubic root of 43218761 is about 350.9329152128.

Adding to 43218761 its reverse (16781234), we get a palindrome (59999995).

The spelling of 43218761 in words is "forty-three million, two hundred eighteen thousand, seven hundred sixty-one".