1820004040 has 32 divisors (see below), whose sum is σ = 4236219000. Its totient is φ = 702897664.

The previous prime is 1820004023. The next prime is 1820004041. The reversal of 1820004040 is 404000281.

It can be written as a sum of positive squares in 4 ways, for example, as 1564835364 + 255168676 = 39558^2 + 15974^2 .

It is a junction number, because it is equal to n+sod(n) for n = 1820003999 and 1820004017.

It is not an unprimeable number, because it can be changed into a prime (1820004041) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 783325 + ... + 785644.

Almost surely, 2^1820004040 is an apocalyptic number.

1820004040 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1820004040 is an abundant number, since it is smaller than the sum of its proper divisors (2416214960).

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

1820004040 is a wasteful number, since it uses less digits than its factorization.

1820004040 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1569009 (or 1569005 counting only the distinct ones).

The product of its (nonzero) digits is 256, while the sum is 19.

The square root of 1820004040 is about 42661.5053649071. The cubic root of 1820004040 is about 1220.9300531443.

The spelling of 1820004040 in words is "one billion, eight hundred twenty million, four thousand, forty".