18694819441 has 9 divisors (see below), whose sum is σ = 18964546209. Its totient is φ = 18428881536.

The previous prime is 18694819399. The next prime is 18694819447. The reversal of 18694819441 is 14491849681.

The square root of 18694819441 is 136729.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in 4 ways, for example, as 5173781041 + 13521038400 = 71929^2 + 116280^2 .

It is not a de Polignac number, because 18694819441 - 2⁹ = 18694818929 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (18694819447) by changing a digit.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 9980281 + ... + 9982153.

It is an arithmetic number, because the mean of its divisors is an integer number (2107171801).

Almost surely, 2^18694819441 is an apocalyptic number.

18694819441 is the 136729-th square number.

18694819441 is the 68365-th centered octagonal number.

It is an amenable number.

18694819441 is a deficient number, since it is larger than the sum of its proper divisors (269726768).

18694819441 is an frugal number, since it uses more digits than its factorization.

18694819441 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3892 (or 1946 counting only the distinct ones).

The product of its digits is 1990656, while the sum is 55.

The spelling of 18694819441 in words is "eighteen billion, six hundred ninety-four million, eight hundred nineteen thousand, four hundred forty-one".