8421555499812 has 864 divisors, whose sum is σ = 30653821699200. Its totient is φ = 1980328476672.

The previous prime is 8421555499807. The next prime is 8421555499837. The reversal of 8421555499812 is 2189945551248.

8421555499812 is a `hidden beast` number, since 8 + 4 + 2 + 1 + 5 + 5 + 549 + 9 + 81 + 2 = 666.

It is a Harshad number since it is a multiple of its sum of digits (63).

It is a self number, because there is not a number n which added to its sum of digits gives 8421555499812.

It is an unprimeable number.

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 287 ways as a sum of consecutive naturals, for example, 288859828 + ... + 288888980.

It is an arithmetic number, because the mean of its divisors is an integer number (35478960300).

Almost surely, 2^{8421555499812} 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 8421555499812, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (15326910849600).

8421555499812 is an abundant number, since it is smaller than the sum of its proper divisors (22232266199388).

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

8421555499812 is a wasteful number, since it uses less digits than its factorization.

8421555499812 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 29242 (or 29214 counting only the distinct ones).

The product of its digits is 41472000, while the sum is 63.

The spelling of 8421555499812 in words is "eight trillion, four hundred twenty-one billion, five hundred fifty-five million, four hundred ninety-nine thousand, eight hundred twelve".