518227921 has 2 divisors, whose sum is σ = 518227922. Its totient is φ = 518227920.

The previous prime is 518227909. The next prime is 518227979. The reversal of 518227921 is 129722815.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 514382400 + 3845521 = 22680^2 + 1961^2 .

It is a cyclic number.

It is not a de Polignac number, because 518227921 - 2⁵ = 518227889 is a prime.

It is not a weakly prime, because it can be changed into another prime (518227991) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 259113960 + 259113961.

It is an arithmetic number, because the mean of its divisors is an integer number (259113961).

Almost surely, 2^518227921 is an apocalyptic number.

It is an amenable number.

518227921 is a deficient number, since it is larger than the sum of its proper divisors (1).

518227921 is an equidigital number, since it uses as much as digits as its factorization.

518227921 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 20160, while the sum is 37.

The square root of 518227921 is about 22764.6199397223. The cubic root of 518227921 is about 803.2306449589.

The spelling of 518227921 in words is "five hundred eighteen million, two hundred twenty-seven thousand, nine hundred twenty-one".