18645952901 has 4 divisors (see below), whose sum is σ = 19149897612. Its totient is φ = 18142008192.

The previous prime is 18645952891. The next prime is 18645952909. The reversal of 18645952901 is 10925954681.

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 6967908676 + 11678044225 = 83474^2 + 108065^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-18645952901 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 18645952901.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18645952909) 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, 251972300 + ... + 251972373.

It is an arithmetic number, because the mean of its divisors is an integer number (4787474403).

Almost surely, 2^18645952901 is an apocalyptic number.

It is an amenable number.

18645952901 is a deficient number, since it is larger than the sum of its proper divisors (503944711).

18645952901 is an equidigital number, since it uses as much as digits as its factorization.

18645952901 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 503944710.

The product of its (nonzero) digits is 777600, while the sum is 50.

The spelling of 18645952901 in words is "eighteen billion, six hundred forty-five million, nine hundred fifty-two thousand, nine hundred one".