821238489 has 12 divisors (see below), whose sum is σ = 1186526016. Its totient is φ = 547357272.

The previous prime is 821238479. The next prime is 821238491. The reversal of 821238489 is 984832128.

It is not a de Polignac number, because 821238489 - 2¹¹ = 821236441 is a prime.

It is not an unprimeable number, because it can be changed into a prime (821238409) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 39124 + ... + 56330.

It is an arithmetic number, because the mean of its divisors is an integer number (98877168).

Almost surely, 2^821238489 is an apocalyptic number.

It is an amenable number.

821238489 is a deficient number, since it is larger than the sum of its proper divisors (365287527).

821238489 is a wasteful number, since it uses less digits than its factorization.

821238489 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 22516 (or 22513 counting only the distinct ones).

The product of its digits is 221184, while the sum is 45.

The square root of 821238489 is about 28657.2589233513. The cubic root of 821238489 is about 936.4611502825.

The spelling of 821238489 in words is "eight hundred twenty-one million, two hundred thirty-eight thousand, four hundred eighty-nine".