1821838489 has 3 divisors (see below), whose sum is σ = 1821881173. Its totient is φ = 1821795806.

The previous prime is 1821838477. The next prime is 1821838517. The reversal of 1821838489 is 9848381281.

It is a happy number.

The square root of 1821838489 is 42683.

It is a perfect power (a square), and thus also a powerful number.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length, and also an emirpimes, since its reverse is a distinct semiprime: 9848381281 = 167 ⋅58972343.

It is not a de Polignac number, because 1821838489 - 2¹⁷ = 1821707417 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1821838429) by changing a digit.

It is a polite number, since it can be written in 2 ways as a sum of consecutive naturals, for example, 21342 + ... + 64024.

Almost surely, 2^1821838489 is an apocalyptic number.

1821838489 is the 42683-rd square number.

1821838489 is the 21342-nd centered octagonal number.

It is an amenable number.

1821838489 is a deficient number, since it is larger than the sum of its proper divisors (42684).

1821838489 is an frugal number, since it uses more digits than its factorization.

1821838489 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 85366 (or 42683 counting only the distinct ones).

The product of its digits is 884736, while the sum is 52.

The cubic root of 1821838489 is about 1221.3401221667.

The spelling of 1821838489 in words is "one billion, eight hundred twenty-one million, eight hundred thirty-eight thousand, four hundred eighty-nine".