821283140520 has 192 divisors, whose sum is σ = 2681484549120. Its totient is φ = 218000627712.

The previous prime is 821283140519. The next prime is 821283140521. The reversal of 821283140520 is 25041382128.

It is a happy number.

821283140520 is a `hidden beast` number, since 8 + 2 + 12 + 83 + 1 + 40 + 520 = 666.

821283140520 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is an interprime number because it is at equal distance from previous prime (821283140519) and next prime (821283140521).

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 (821283140521) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 78488809 + ... + 78499271.

It is an arithmetic number, because the mean of its divisors is an integer number (13966065360).

Almost surely, 2^821283140520 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 821283140520, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1340742274560).

821283140520 is an abundant number, since it is smaller than the sum of its proper divisors (1860201408600).

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

821283140520 is a wasteful number, since it uses less digits than its factorization.

821283140520 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11464 (or 11457 counting only the distinct ones).

The product of its (nonzero) digits is 30720, while the sum is 36.

The spelling of 821283140520 in words is "eight hundred twenty-one billion, two hundred eighty-three million, one hundred forty thousand, five hundred twenty".