618446440123361 has 4 divisors (see below), whose sum is σ = 618824232696852. Its totient is φ = 618068647549872.

The previous prime is 618446440123357. The next prime is 618446440123381. The reversal of 618446440123361 is 163321044644816.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 45637320691600 + 572809119431761 = 6755540^2 + 23933431^2 .

It is a cyclic number.

It is not a de Polignac number, because 618446440123361 - 2² = 618446440123357 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (618446440123381) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 188896284290 + ... + 188896287563.

It is an arithmetic number, because the mean of its divisors is an integer number (154706058174213).

Almost surely, 2^{618446440123361} is an apocalyptic number.

It is an amenable number.

618446440123361 is a deficient number, since it is larger than the sum of its proper divisors (377792573491).

618446440123361 is a wasteful number, since it uses less digits than its factorization.

618446440123361 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 377792573490.

The product of its (nonzero) digits is 7962624, while the sum is 53.

The spelling of 618446440123361 in words is "six hundred eighteen trillion, four hundred forty-six billion, four hundred forty million, one hundred twenty-three thousand, three hundred sixty-one".