840606656 has 112 divisors (see below), whose sum is σ = 1787444736. Its totient is φ = 391716864.

The previous prime is 840606643. The next prime is 840606677. The reversal of 840606656 is 656606048.

It is a super-2 number, since 2×840606656² = 1413239100223004672, which contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 8666000 + ... + 8666096.

It is an arithmetic number, because the mean of its divisors is an integer number (15959328).

Almost surely, 2^840606656 is an apocalyptic number.

840606656 is a gapful number since it is divisible by the number (86) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 840606656, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (893722368).

840606656 is an abundant number, since it is smaller than the sum of its proper divisors (946838080).

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

840606656 is a wasteful number, since it uses less digits than its factorization.

840606656 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 266 (or 256 counting only the distinct ones).

The product of its (nonzero) digits is 207360, while the sum is 41.

The square root of 840606656 is about 28993.2174137332. The cubic root of 840606656 is about 943.7658856382.

The spelling of 840606656 in words is "eight hundred forty million, six hundred six thousand, six hundred fifty-six".