821268 has 36 divisors (see below), whose sum is σ = 2373280. Its totient is φ = 234576.

The previous prime is 821263. The next prime is 821281. The reversal of 821268 is 862128.

It is a tau number, because it is divible by the number of its divisors (36).

It is a super-2 number, since 2×821268² = 1348962255648, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (821263) by changing a digit.

821268 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1378 + ... + 1881.

2⁸²¹²⁶⁸ is an apocalyptic number.

It is an amenable number.

821268 is an abundant number, since it is smaller than the sum of its proper divisors (1552012).

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

821268 is a wasteful number, since it uses less digits than its factorization.

821268 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3276 (or 3271 counting only the distinct ones).

The product of its digits is 1536, while the sum is 27.

The square root of 821268 is about 906.2383792358. The cubic root of 821268 is about 93.6472367314.

It can be divided in two parts, 821 and 268, that added together give a square (1089 = 33²).

The spelling of 821268 in words is "eight hundred twenty-one thousand, two hundred sixty-eight".