821002 has 24 divisors (see below), whose sum is σ = 1528416. Its totient is φ = 323856.

The previous prime is 820997. The next prime is 821003. The reversal of 821002 is 200128.

It is a Harshad number since it is a multiple of its sum of digits (13).

It is a zygodrome in base 13.

It is not an unprimeable number, because it can be changed into a prime (821003) 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, 2193 + ... + 2539.

It is an arithmetic number, because the mean of its divisors is an integer number (63684).

2⁸²¹⁰⁰² is an apocalyptic number.

821002 is a deficient number, since it is larger than the sum of its proper divisors (707414).

821002 is a wasteful number, since it uses less digits than its factorization.

821002 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 382 (or 369 counting only the distinct ones).

The product of its (nonzero) digits is 32, while the sum is 13.

The square root of 821002 is about 906.0916068478. The cubic root of 821002 is about 93.6371251905.

The spelling of 821002 in words is "eight hundred twenty-one thousand, two".