1813625389 has 4 divisors (see below), whose sum is σ = 1814575356. Its totient is φ = 1812675424.

The previous prime is 1813625383. The next prime is 1813625413. The reversal of 1813625389 is 9835263181.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 1379528164 + 434097225 = 37142^2 + 20835^2 .

It is a cyclic number.

It is not a de Polignac number, because 1813625389 - 2²³ = 1805236781 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1813625383) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 472114 + ... + 475939.

It is an arithmetic number, because the mean of its divisors is an integer number (453643839).

Almost surely, 2^1813625389 is an apocalyptic number.

It is an amenable number.

1813625389 is a deficient number, since it is larger than the sum of its proper divisors (949967).

1813625389 is an equidigital number, since it uses as much as digits as its factorization.

1813625389 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 949966.

The product of its digits is 311040, while the sum is 46.

The square root of 1813625389 is about 42586.6808873385. The cubic root of 1813625389 is about 1219.5020338512.

The spelling of 1813625389 in words is "one billion, eight hundred thirteen million, six hundred twenty-five thousand, three hundred eighty-nine".