840478540 has 24 divisors (see below), whose sum is σ = 1925460432. Its totient is φ = 305628480.

The previous prime is 840478511. The next prime is 840478543. The reversal of 840478540 is 45874048.

It is a junction number, because it is equal to n+sod(n) for n = 840478493 and 840478502.

It is not an unprimeable number, because it can be changed into a prime (840478543) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1909959 + ... + 1910398.

It is an arithmetic number, because the mean of its divisors is an integer number (80227518).

Almost surely, 2^840478540 is an apocalyptic number.

It is an amenable number.

840478540 is an abundant number, since it is smaller than the sum of its proper divisors (1084981892).

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

840478540 is a wasteful number, since it uses less digits than its factorization.

840478540 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3820377 (or 3820375 counting only the distinct ones).

The product of its (nonzero) digits is 143360, while the sum is 40.

The square root of 840478540 is about 28991.0079162488. The cubic root of 840478540 is about 943.7179370713.

The spelling of 840478540 in words is "eight hundred forty million, four hundred seventy-eight thousand, five hundred forty".