1819861878648 has 256 divisors, whose sum is σ = 5394715084800. Its totient is φ = 505436405760.

The previous prime is 1819861878643. The next prime is 1819861878713. The reversal of 1819861878648 is 8468781689181.

It is a self number, because there is not a number n which added to its sum of digits gives 1819861878648.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1819861878643) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 25847140 + ... + 25917452.

It is an arithmetic number, because the mean of its divisors is an integer number (21073105800).

Almost surely, 2^{1819861878648} 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 1819861878648, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2697357542400).

1819861878648 is an abundant number, since it is smaller than the sum of its proper divisors (3574853206152).

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

1819861878648 is a wasteful number, since it uses less digits than its factorization.

1819861878648 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 70502 (or 70498 counting only the distinct ones).

The product of its digits is 297271296, while the sum is 75.

The spelling of 1819861878648 in words is "one trillion, eight hundred nineteen billion, eight hundred sixty-one million, eight hundred seventy-eight thousand, six hundred forty-eight".