819855477648 has 60 divisors (see below), whose sum is σ = 2299433964828. Its totient is φ = 272692327680.

The previous prime is 819855477641. The next prime is 819855477673. The reversal of 819855477648 is 846774558918.

It is a happy number.

819855477648 is a `hidden beast` number, since 8 + 1 + 9 + 8 + 5 + 547 + 76 + 4 + 8 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 154958747904 + 664896729744 = 393648^2 + 815412^2 .

It is a super-2 number, since 2×819855477648² (a number of 25 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (72).

It is not an unprimeable number, because it can be changed into a prime (819855477641) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 6108715 + ... + 6241482.

Almost surely, 2^819855477648 is an apocalyptic number.

It is an amenable number.

819855477648 is an abundant number, since it is smaller than the sum of its proper divisors (1479578487180).

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

819855477648 is a wasteful number, since it uses less digits than its factorization.

819855477648 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12350672 (or 12350663 counting only the distinct ones).

The product of its digits is 541900800, while the sum is 72.

The spelling of 819855477648 in words is "eight hundred nineteen billion, eight hundred fifty-five million, four hundred seventy-seven thousand, six hundred forty-eight".