18938590145 has 4 divisors (see below), whose sum is σ = 22726308180. Its totient is φ = 15150872112.

The previous prime is 18938590133. The next prime is 18938590163. The reversal of 18938590145 is 54109583981.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 54109583981 = 31 ⋅1745470451.

It can be written as a sum of positive squares in 2 ways, for example, as 4778542129 + 14160048016 = 69127^2 + 118996^2 .

It is a cyclic number.

It is not a de Polignac number, because 18938590145 - 2²⁰ = 18937541569 is a prime.

It is a super-2 number, since 2×18938590145² (a number of 21 digits) contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1893859010 + ... + 1893859019.

It is an arithmetic number, because the mean of its divisors is an integer number (5681577045).

Almost surely, 2^18938590145 is an apocalyptic number.

It is an amenable number.

18938590145 is a deficient number, since it is larger than the sum of its proper divisors (3787718035).

18938590145 is an equidigital number, since it uses as much as digits as its factorization.

18938590145 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3787718034.

The product of its (nonzero) digits is 1555200, while the sum is 53.

The spelling of 18938590145 in words is "eighteen billion, nine hundred thirty-eight million, five hundred ninety thousand, one hundred forty-five".