1812936636 has 144 divisors (see below), whose sum is σ = 5500744704. Its totient is φ = 492231168.

The previous prime is 1812936589. The next prime is 1812936667. The reversal of 1812936636 is 6366392181.

1812936636 is a `hidden beast` number, since 1 + 8 + 1 + 2 + 9 + 3 + 6 + 636 = 666.

It is a junction number, because it is equal to n+sod(n) for n = 1812936591 and 1812936600.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 966996 + ... + 968868.

It is an arithmetic number, because the mean of its divisors is an integer number (38199616).

Almost surely, 2^1812936636 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1812936636, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2750372352).

1812936636 is an abundant number, since it is smaller than the sum of its proper divisors (3687808068).

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

1812936636 is a wasteful number, since it uses less digits than its factorization.

1812936636 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2080 (or 2075 counting only the distinct ones).

The product of its digits is 279936, while the sum is 45.

The square root of 1812936636 is about 42578.5936357696. The cubic root of 1812936636 is about 1219.3476392266.

The spelling of 1812936636 in words is "one billion, eight hundred twelve million, nine hundred thirty-six thousand, six hundred thirty-six".