18642625444 has 27 divisors (see below), whose sum is σ = 32877423523. Its totient is φ = 9249630272.

The previous prime is 18642625433. The next prime is 18642625451. The reversal of 18642625444 is 44452624681.

The square root of 18642625444 is 136538.

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 996159844 + 17646465600 = 31562^2 + 132840^2 .

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 18642625394 and 18642625403.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 63626562 + ... + 63626854.

Almost surely, 2^18642625444 is an apocalyptic number.

18642625444 is the 136538-th square number.

It is an amenable number.

18642625444 is a deficient number, since it is larger than the sum of its proper divisors (14234798079).

18642625444 is an frugal number, since it uses more digits than its factorization.

18642625444 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1056 (or 528 counting only the distinct ones).

The product of its digits is 1474560, while the sum is 46.

The spelling of 18642625444 in words is "eighteen billion, six hundred forty-two million, six hundred twenty-five thousand, four hundred forty-four".