821898 has 48 divisors (see below), whose sum is σ = 2223936. Its totient is φ = 213120.

The previous prime is 821897. The next prime is 821911. The reversal of 821898 is 898128.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (821897) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 1090 + ... + 1682.

It is an arithmetic number, because the mean of its divisors is an integer number (46332).

2⁸²¹⁸⁹⁸ is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 821898, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1111968).

821898 is an abundant number, since it is smaller than the sum of its proper divisors (1402038).

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

821898 is a wasteful number, since it uses less digits than its factorization.

821898 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 619 (or 616 counting only the distinct ones).

The product of its digits is 9216, while the sum is 36.

The square root of 821898 is about 906.5859032657. The cubic root of 821898 is about 93.6711764116.

The spelling of 821898 in words is "eight hundred twenty-one thousand, eight hundred ninety-eight".