840440408440 has 16 divisors (see below), whose sum is σ = 1890990919080. Its totient is φ = 336176163360.

The previous prime is 840440408417. The next prime is 840440408461. The reversal of 840440408440 is 44804044048.

It is a Harshad number since it is a multiple of its sum of digits (40), and also a Moran number because the ratio is a prime number: 21011010211 = 840440408440 / (8 + 4 + 0 + 4 + 4 + 0 + 4 + 0 + 8 + 4 + 4 + 0).

It is a junction number, because it is equal to n+sod(n) for n = 840440408393 and 840440408402.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 10505505066 + ... + 10505505145.

Almost surely, 2^840440408440 is an apocalyptic number.

It is an amenable number.

840440408440 is an abundant number, since it is smaller than the sum of its proper divisors (1050550510640).

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

840440408440 is a wasteful number, since it uses less digits than its factorization.

840440408440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21011010222 (or 21011010218 counting only the distinct ones).

The product of its (nonzero) digits is 262144, while the sum is 40.

The spelling of 840440408440 in words is "eight hundred forty billion, four hundred forty million, four hundred eight thousand, four hundred forty".