43821020 has 12 divisors (see below), whose sum is σ = 92024184. Its totient is φ = 17528400.

The previous prime is 43821017. The next prime is 43821023. The reversal of 43821020 is 2012834.

It is an interprime number because it is at equal distance from previous prime (43821017) and next prime (43821023).

It is a Harshad number since it is a multiple of its sum of digits (20), and also a Moran number because the ratio is a prime number: 2191051 = 43821020 / (4 + 3 + 8 + 2 + 1 + 0 + 2 + 0).

It is a junction number, because it is equal to n+sod(n) for n = 43820983 and 43821001.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (43821023) 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, 1095506 + ... + 1095545.

It is an arithmetic number, because the mean of its divisors is an integer number (7668682).

Almost surely, 2^43821020 is an apocalyptic number.

It is an amenable number.

43821020 is an abundant number, since it is smaller than the sum of its proper divisors (48203164).

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

43821020 is a wasteful number, since it uses less digits than its factorization.

43821020 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2191060 (or 2191058 counting only the distinct ones).

The product of its (nonzero) digits is 384, while the sum is 20.

The square root of 43821020 is about 6619.7447080684. The cubic root of 43821020 is about 352.5554998708. Note that the first 3 decimals are identical.

Adding to 43821020 its reverse (2012834), we get a palindrome (45833854).

The spelling of 43821020 in words is "forty-three million, eight hundred twenty-one thousand, twenty".