821552255128 has 16 divisors (see below), whose sum is σ = 1680447794760. Its totient is φ = 373432843200.

The previous prime is 821552255123. The next prime is 821552255129.

821552255128 is nontrivially palindromic in base 10.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (821552255123) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4667910453 + ... + 4667910628.

Almost surely, 2^821552255128 is an apocalyptic number.

821552255128 is a gapful number since it is divisible by the number (88) formed by its first and last digit.

It is an amenable number.

821552255128 is an abundant number, since it is smaller than the sum of its proper divisors (858895539632).

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

821552255128 is a wasteful number, since it uses less digits than its factorization.

821552255128 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9335821098 (or 9335821094 counting only the distinct ones).

The product of its digits is 640000, while the sum is 46.

The spelling of 821552255128 in words is "eight hundred twenty-one billion, five hundred fifty-two million, two hundred fifty-five thousand, one hundred twenty-eight".