840128544 has 192 divisors, whose sum is σ = 2599188480. Its totient is φ = 263450880.

The previous prime is 840128537. The next prime is 840128557. The reversal of 840128544 is 445821048.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 840128499 and 840128508.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1331109 + ... + 1331739.

It is an arithmetic number, because the mean of its divisors is an integer number (13537440).

Almost surely, 2^840128544 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 840128544, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1299594240).

840128544 is an abundant number, since it is smaller than the sum of its proper divisors (1759059936).

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

840128544 is a wasteful number, since it uses less digits than its factorization.

840128544 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 740 (or 726 counting only the distinct ones).

The product of its (nonzero) digits is 40960, while the sum is 36.

The square root of 840128544 is about 28984.9710022280. The cubic root of 840128544 is about 943.5869230731.

The spelling of 840128544 in words is "eight hundred forty million, one hundred twenty-eight thousand, five hundred forty-four".