2043321021 has 18 divisors (see below), whose sum is σ = 3433336062. Its totient is φ = 1167611760.

The previous prime is 2043321019. The next prime is 2043321023. The reversal of 2043321021 is 1201233402.

2043321021 is a `hidden beast` number, since 2 + 0 + 433 + 210 + 21 = 666.

It is an interprime number because it is at equal distance from previous prime (2043321019) and next prime (2043321023).

It can be written as a sum of positive squares in only one way, i.e., 1649496996 + 393824025 = 40614^2 + 19845^2 .

It is not a de Polignac number, because 2043321021 - 2¹ = 2043321019 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 2043320985 and 2043321003.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2043321023) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 2316250 + ... + 2317131.

Almost surely, 2^2043321021 is an apocalyptic number.

2043321021 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

It is an amenable number.

2043321021 is a deficient number, since it is larger than the sum of its proper divisors (1390015041).

2043321021 is a wasteful number, since it uses less digits than its factorization.

2043321021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4633401 (or 4633391 counting only the distinct ones).

The product of its (nonzero) digits is 288, while the sum is 18.

The square root of 2043321021 is about 45203.1085324892. The cubic root of 2043321021 is about 1268.9529926494.

Adding to 2043321021 its reverse (1201233402), we get a palindrome (3244554423).

The spelling of 2043321021 in words is "two billion, forty-three million, three hundred twenty-one thousand, twenty-one".