840941640 has 384 divisors, whose sum is σ = 3558297600. Its totient is φ = 167016960.

The previous prime is 840941627. The next prime is 840941657. The reversal of 840941640 is 46149048.

It is a happy number.

840941640 is a `hidden beast` number, since 8 + 4 + 0 + 9 + 4 + 1 + 640 = 666.

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 = 840941595 and 840941604.

It is an unprimeable number.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 636901 + ... + 638219.

It is an arithmetic number, because the mean of its divisors is an integer number (9266400).

Almost surely, 2^840941640 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 840941640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1779148800).

840941640 is an abundant number, since it is smaller than the sum of its proper divisors (2717355960).

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

840941640 is a wasteful number, since it uses less digits than its factorization.

840941640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1377 (or 1370 counting only the distinct ones).

The product of its (nonzero) digits is 27648, while the sum is 36.

The square root of 840941640 is about 28998.9937756468. The cubic root of 840941640 is about 943.8912333988.

The spelling of 840941640 in words is "eight hundred forty million, nine hundred forty-one thousand, six hundred forty".