18220402481 has 2 divisors, whose sum is σ = 18220402482. Its totient is φ = 18220402480.

The previous prime is 18220402441. The next prime is 18220402531. The reversal of 18220402481 is 18420402281.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 15287096881 + 2933305600 = 123641^2 + 54160^2 .

It is an emirp because it is prime and its reverse (18420402281) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-18220402481 is a prime.

It is a super-2 number, since 2×18220402481² (a number of 21 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (18220402411) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9110201240 + 9110201241.

It is an arithmetic number, because the mean of its divisors is an integer number (9110201241).

Almost surely, 2^18220402481 is an apocalyptic number.

It is an amenable number.

18220402481 is a deficient number, since it is larger than the sum of its proper divisors (1).

18220402481 is an equidigital number, since it uses as much as digits as its factorization.

18220402481 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 8192, while the sum is 32.

The spelling of 18220402481 in words is "eighteen billion, two hundred twenty million, four hundred two thousand, four hundred eighty-one".