1618181 has 2 divisors, whose sum is σ = 1618182. Its totient is φ = 1618180.

The previous prime is 1618153. The next prime is 1618187. The reversal of 1618181 is 1818161.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1600225 + 17956 = 1265^2 + 134^2 .

It is an emirp because it is prime and its reverse (1818161) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1618181 - 2¹⁴ = 1601797 is a prime.

It is a super-2 number, since 2×1618181² = 5237019497522, which contains 22 as substring.

It is a Chen prime.

It is an alternating number because its digits alternate between odd and even.

It is a self number, because there is not a number n which added to its sum of digits gives 1618181.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1618187) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 809090 + 809091.

It is an arithmetic number, because the mean of its divisors is an integer number (809091).

2^1618181 is an apocalyptic number.

It is an amenable number.

1618181 is a deficient number, since it is larger than the sum of its proper divisors (1).

1618181 is an equidigital number, since it uses as much as digits as its factorization.

1618181 is an evil number, because the sum of its binary digits is even.

The product of its digits is 384, while the sum is 26.

The square root of 1618181 is about 1272.0774347499. The cubic root of 1618181 is about 117.4020550918.

The spelling of 1618181 in words is "one million, six hundred eighteen thousand, one hundred eighty-one".