821652998985 has 120 divisors (see below), whose sum is σ = 1822747988160. Its totient is φ = 346719305088.

The previous prime is 821652998983. The next prime is 821652998989. The reversal of 821652998985 is 589899256128.

821652998985 is a `hidden beast` number, since 8 + 2 + 1 + 6 + 529 + 9 + 8 + 98 + 5 = 666.

It is not a de Polignac number, because 821652998985 - 2¹ = 821652998983 is a prime.

It is a super-2 number, since 2×821652998985² (a number of 25 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (821652998983) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 119 ways as a sum of consecutive naturals, for example, 378355 + ... + 1336584.

It is an arithmetic number, because the mean of its divisors is an integer number (15189566568).

Almost surely, 2^821652998985 is an apocalyptic number.

It is an amenable number.

821652998985 is an abundant number, since it is smaller than the sum of its proper divisors (1001094989175).

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

821652998985 is a wasteful number, since it uses less digits than its factorization.

821652998985 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1714989 (or 1714967 counting only the distinct ones).

The product of its digits is 223948800, while the sum is 72.

The spelling of 821652998985 in words is "eight hundred twenty-one billion, six hundred fifty-two million, nine hundred ninety-eight thousand, nine hundred eighty-five".