821315264 has 168 divisors, whose sum is σ = 2142164880. Its totient is φ = 308582400.

The previous prime is 821315221. The next prime is 821315281. The reversal of 821315264 is 462513128.

It is a Harshad number since it is a multiple of its sum of digits (32).

It is a self number, because there is not a number n which added to its sum of digits gives 821315264.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 999974 + ... + 1000794.

Almost surely, 2^821315264 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 821315264, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1071082440).

821315264 is an abundant number, since it is smaller than the sum of its proper divisors (1320849616).

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

821315264 is a wasteful number, since it uses less digits than its factorization.

821315264 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 887 (or 870 counting only the distinct ones).

The product of its digits is 11520, while the sum is 32.

The square root of 821315264 is about 28658.5984304885. The cubic root of 821315264 is about 936.4903316411.

The spelling of 821315264 in words is "eight hundred twenty-one million, three hundred fifteen thousand, two hundred sixty-four".