618891601 has 2 divisors, whose sum is σ = 618891602. Its totient is φ = 618891600.

The previous prime is 618891589. The next prime is 618891607. The reversal of 618891601 is 106198816.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 565250625 + 53640976 = 23775^2 + 7324^2 .

It is a cyclic number.

It is not a de Polignac number, because 618891601 - 2⁵ = 618891569 is a prime.

It is not a weakly prime, because it can be changed into another prime (618891607) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 309445800 + 309445801.

It is an arithmetic number, because the mean of its divisors is an integer number (309445801).

Almost surely, 2^618891601 is an apocalyptic number.

It is an amenable number.

618891601 is a deficient number, since it is larger than the sum of its proper divisors (1).

618891601 is an equidigital number, since it uses as much as digits as its factorization.

618891601 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 20736, while the sum is 40.

The square root of 618891601 is about 24877.5320520344. The cubic root of 618891601 is about 852.1934586994.

The spelling of 618891601 in words is "six hundred eighteen million, eight hundred ninety-one thousand, six hundred one".