618161 has 2 divisors, whose sum is σ = 618162. Its totient is φ = 618160.

The previous prime is 618131. The next prime is 618173. The reversal of 618161 is 161816.

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., 616225 + 1936 = 785^2 + 44^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-618161 is a prime.

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

It is not a weakly prime, because it can be changed into another prime (618131) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 309080 + 309081.

It is an arithmetic number, because the mean of its divisors is an integer number (309081).

2⁶¹⁸¹⁶¹ is an apocalyptic number.

It is an amenable number.

618161 is a deficient number, since it is larger than the sum of its proper divisors (1).

618161 is an equidigital number, since it uses as much as digits as its factorization.

618161 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 288, while the sum is 23.

The square root of 618161 is about 786.2321540105. The cubic root of 618161 is about 85.1857988777.

Adding to 618161 its reverse (161816), we get a palindrome (779977).

The spelling of 618161 in words is "six hundred eighteen thousand, one hundred sixty-one".