618810121 has 2 divisors, whose sum is σ = 618810122. Its totient is φ = 618810120.

The previous prime is 618810079. The next prime is 618810151. The reversal of 618810121 is 121018816.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 593166025 + 25644096 = 24355^2 + 5064^2 .

It is a cyclic number.

It is not a de Polignac number, because 618810121 - 2¹³ = 618801929 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 618810121.

It is not a weakly prime, because it can be changed into another prime (618810151) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 309405060 + 309405061.

It is an arithmetic number, because the mean of its divisors is an integer number (309405061).

Almost surely, 2^618810121 is an apocalyptic number.

It is an amenable number.

618810121 is a deficient number, since it is larger than the sum of its proper divisors (1).

618810121 is an equidigital number, since it uses as much as digits as its factorization.

618810121 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 768, while the sum is 28.

The square root of 618810121 is about 24875.8943758812. The cubic root of 618810121 is about 852.1560586279.

Adding to 618810121 its reverse (121018816), we get a palindrome (739828937).

The spelling of 618810121 in words is "six hundred eighteen million, eight hundred ten thousand, one hundred twenty-one".