840478386 has 64 divisors (see below), whose sum is σ = 1901039616. Its totient is φ = 245419200.

The previous prime is 840478381. The next prime is 840478391. The reversal of 840478386 is 683874048.

It is an interprime number because it is at equal distance from previous prime (840478381) and next prime (840478391).

It is not an unprimeable number, because it can be changed into a prime (840478381) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 566001 + ... + 567483.

It is an arithmetic number, because the mean of its divisors is an integer number (29703744).

Almost surely, 2^840478386 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 840478386, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (950519808).

840478386 is an abundant number, since it is smaller than the sum of its proper divisors (1060561230).

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

840478386 is a wasteful number, since it uses less digits than its factorization.

840478386 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1807.

The product of its (nonzero) digits is 1032192, while the sum is 48.

The square root of 840478386 is about 28991.0052602527. The cubic root of 840478386 is about 943.7178794325.

The spelling of 840478386 in words is "eight hundred forty million, four hundred seventy-eight thousand, three hundred eighty-six".