18875349221 has 2 divisors, whose sum is σ = 18875349222. Its totient is φ = 18875349220.

The previous prime is 18875349217. The next prime is 18875349281. The reversal of 18875349221 is 12294357881.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 17066548321 + 1808800900 = 130639^2 + 42530^2 .

It is a cyclic number.

It is not a de Polignac number, because 18875349221 - 2² = 18875349217 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 18875349221.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (18875349281) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9437674610 + 9437674611.

It is an arithmetic number, because the mean of its divisors is an integer number (9437674611).

Almost surely, 2^18875349221 is an apocalyptic number.

It is an amenable number.

18875349221 is a deficient number, since it is larger than the sum of its proper divisors (1).

18875349221 is an equidigital number, since it uses as much as digits as its factorization.

18875349221 is an evil number, because the sum of its binary digits is even.

The product of its digits is 967680, while the sum is 50.

The spelling of 18875349221 in words is "eighteen billion, eight hundred seventy-five million, three hundred forty-nine thousand, two hundred twenty-one".