1813591945 has 16 divisors (see below), whose sum is σ = 2387286720. Its totient is φ = 1311681600.

The previous prime is 1813591931. The next prime is 1813591957. The reversal of 1813591945 is 5491953181.

It is not a de Polignac number, because 1813591945 - 2¹³ = 1813583753 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 1813591895 and 1813591904.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 81135 + ... + 101044.

It is an arithmetic number, because the mean of its divisors is an integer number (149205420).

Almost surely, 2^1813591945 is an apocalyptic number.

It is an amenable number.

1813591945 is a deficient number, since it is larger than the sum of its proper divisors (573694775).

1813591945 is a wasteful number, since it uses less digits than its factorization.

1813591945 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 182376.

The product of its digits is 194400, while the sum is 46.

The square root of 1813591945 is about 42586.2882275504. The cubic root of 1813591945 is about 1219.4945377650.

The spelling of 1813591945 in words is "one billion, eight hundred thirteen million, five hundred ninety-one thousand, nine hundred forty-five".