1813891308 has 12 divisors (see below), whose sum is σ = 4232413080. Its totient is φ = 604630432.

The previous prime is 1813891307. The next prime is 1813891337. The reversal of 1813891308 is 8031983181.

It is a tau number, because it is divible by the number of its divisors (12).

It is a Smith number, since the sum of its digits (42) coincides with the sum of the digits of its prime factors.

It is a self number, because there is not a number n which added to its sum of digits gives 1813891308.

It is not an unprimeable number, because it can be changed into a prime (1813891301) 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, 75578793 + ... + 75578816.

It is an arithmetic number, because the mean of its divisors is an integer number (352701090).

Almost surely, 2^1813891308 is an apocalyptic number.

It is an amenable number.

1813891308 is an abundant number, since it is smaller than the sum of its proper divisors (2418521772).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1813891308 is a wasteful number, since it uses less digits than its factorization.

1813891308 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 151157616 (or 151157614 counting only the distinct ones).

The product of its (nonzero) digits is 41472, while the sum is 42.

The square root of 1813891308 is about 42589.8028640659. The cubic root of 1813891308 is about 1219.5616332435.

The spelling of 1813891308 in words is "one billion, eight hundred thirteen million, eight hundred ninety-one thousand, three hundred eight".