918718022221 has 2 divisors, whose sum is σ = 918718022222. Its totient is φ = 918718022220.

The previous prime is 918718022203. The next prime is 918718022231. The reversal of 918718022221 is 122220817819.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 918695412196 + 22610025 = 958486^2 + 4755^2 .

It is a cyclic number.

It is not a de Polignac number, because 918718022221 - 2⁷ = 918718022093 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (918718022231) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 459359011110 + 459359011111.

It is an arithmetic number, because the mean of its divisors is an integer number (459359011111).

Almost surely, 2^918718022221 is an apocalyptic number.

It is an amenable number.

918718022221 is a deficient number, since it is larger than the sum of its proper divisors (1).

918718022221 is an equidigital number, since it uses as much as digits as its factorization.

918718022221 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 64512, while the sum is 43.

The spelling of 918718022221 in words is "nine hundred eighteen billion, seven hundred eighteen million, twenty-two thousand, two hundred twenty-one".