1818580681 has 2 divisors, whose sum is σ = 1818580682. Its totient is φ = 1818580680.

The previous prime is 1818580663. The next prime is 1818580693. The reversal of 1818580681 is 1860858181.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1162196281 + 656384400 = 34091^2 + 25620^2 .

It is a cyclic number.

It is not a de Polignac number, because 1818580681 - 2¹³ = 1818572489 is a prime.

It is a super-2 number, since 2×1818580681² = 6614471386612847522, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (1818580601) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 909290340 + 909290341.

It is an arithmetic number, because the mean of its divisors is an integer number (909290341).

Almost surely, 2^1818580681 is an apocalyptic number.

It is an amenable number.

1818580681 is a deficient number, since it is larger than the sum of its proper divisors (1).

1818580681 is an equidigital number, since it uses as much as digits as its factorization.

1818580681 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 122880, while the sum is 46.

The square root of 1818580681 is about 42644.8200957631. The cubic root of 1818580681 is about 1220.6116884653.

The spelling of 1818580681 in words is "one billion, eight hundred eighteen million, five hundred eighty thousand, six hundred eighty-one".