1805000020 has 24 divisors (see below), whose sum is σ = 3921208200. Its totient is φ = 697103232.

The previous prime is 1804999969. The next prime is 1805000051. The reversal of 1805000020 is 200005081.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 207878724 + 1597121296 = 14418^2 + 39964^2 .

It is a junction number, because it is equal to n+sod(n) for n = 1804999958 and 1805000003.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1555455 + ... + 1556614.

It is an arithmetic number, because the mean of its divisors is an integer number (163383675).

Almost surely, 2^1805000020 is an apocalyptic number.

1805000020 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1805000020 is an abundant number, since it is smaller than the sum of its proper divisors (2116208180).

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

1805000020 is a wasteful number, since it uses less digits than its factorization.

1805000020 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3112107 (or 3112105 counting only the distinct ones).

The product of its (nonzero) digits is 80, while the sum is 16.

The square root of 1805000020 is about 42485.2918078716. The cubic root of 1805000020 is about 1217.5656960194.

It can be divided in two parts, 18050000 and 20, that multiplied together give a square (361000000 = 19000²).

The spelling of 1805000020 in words is "one billion, eight hundred five million, twenty", and thus it is an aban number.