821363724 has 72 divisors (see below), whose sum is σ = 2151746688. Its totient is φ = 263900160.

The previous prime is 821363717. The next prime is 821363729. The reversal of 821363724 is 427363128.

It is a happy number.

821363724 is a `hidden beast` number, since 8 + 2 + 13 + 637 + 2 + 4 = 666.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is not an unprimeable number, because it can be changed into a prime (821363729) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 307804 + ... + 310460.

Almost surely, 2^821363724 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 821363724, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1075873344).

821363724 is an abundant number, since it is smaller than the sum of its proper divisors (1330382964).

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

821363724 is a wasteful number, since it uses less digits than its factorization.

821363724 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2975 (or 2970 counting only the distinct ones).

The product of its digits is 48384, while the sum is 36.

The square root of 821363724 is about 28659.4438885335. The cubic root of 821363724 is about 936.5087498340.

The spelling of 821363724 in words is "eight hundred twenty-one million, three hundred sixty-three thousand, seven hundred twenty-four".