18441978253 has 2 divisors, whose sum is σ = 18441978254. Its totient is φ = 18441978252.

The previous prime is 18441978127. The next prime is 18441978281. The reversal of 18441978253 is 35287914481.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 18427248009 + 14730244 = 135747^2 + 3838^2 .

It is a cyclic number.

It is not a de Polignac number, because 18441978253 - 2²⁵ = 18408423821 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 18441978253.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (18441978853) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9220989126 + 9220989127.

It is an arithmetic number, because the mean of its divisors is an integer number (9220989127).

Almost surely, 2^18441978253 is an apocalyptic number.

It is an amenable number.

18441978253 is a deficient number, since it is larger than the sum of its proper divisors (1).

18441978253 is an equidigital number, since it uses as much as digits as its factorization.

18441978253 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1935360, while the sum is 52.

The spelling of 18441978253 in words is "eighteen billion, four hundred forty-one million, nine hundred seventy-eight thousand, two hundred fifty-three".