18046821601 has 4 divisors (see below), whose sum is σ = 18104479492. Its totient is φ = 17989163712.

The previous prime is 18046821589. The next prime is 18046821643. The reversal of 18046821601 is 10612864081.

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 2233507600 + 15813314001 = 47260^2 + 125751^2 .

It is a cyclic number.

It is not a de Polignac number, because 18046821601 - 2¹³ = 18046813409 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (18046821101) 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, 28828476 + ... + 28829101.

It is an arithmetic number, because the mean of its divisors is an integer number (4526119873).

Almost surely, 2^18046821601 is an apocalyptic number.

It is an amenable number.

18046821601 is a deficient number, since it is larger than the sum of its proper divisors (57657891).

18046821601 is an equidigital number, since it uses as much as digits as its factorization.

18046821601 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 57657890.

The product of its (nonzero) digits is 18432, while the sum is 37.

The spelling of 18046821601 in words is "eighteen billion, forty-six million, eight hundred twenty-one thousand, six hundred one".