821393182505 has 48 divisors (see below), whose sum is σ = 1193799345024. Its totient is φ = 531171164160.

The previous prime is 821393182499. The next prime is 821393182523. The reversal of 821393182505 is 505281393128.

It is not a de Polignac number, because 821393182505 - 2⁸ = 821393182249 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 821393182505.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 941225 + ... + 1590185.

It is an arithmetic number, because the mean of its divisors is an integer number (24870819688).

Almost surely, 2^821393182505 is an apocalyptic number.

It is an amenable number.

821393182505 is a deficient number, since it is larger than the sum of its proper divisors (372406162519).

821393182505 is a wasteful number, since it uses less digits than its factorization.

821393182505 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 649074 (or 649045 counting only the distinct ones).

The product of its (nonzero) digits is 518400, while the sum is 47.

The spelling of 821393182505 in words is "eight hundred twenty-one billion, three hundred ninety-three million, one hundred eighty-two thousand, five hundred five".