840649040 has 160 divisors (see below), whose sum is σ = 2451271680. Its totient is φ = 260467200.

The previous prime is 840649037. The next prime is 840649049. The reversal of 840649040 is 40946048.

It is a Harshad number since it is a multiple of its sum of digits (35).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (840649049) 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, 1471955 + ... + 1472525.

It is an arithmetic number, because the mean of its divisors is an integer number (15320448).

Almost surely, 2^840649040 is an apocalyptic number.

840649040 is a gapful number since it is divisible by the number (80) 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 840649040, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1225635840).

840649040 is an abundant number, since it is smaller than the sum of its proper divisors (1610622640).

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

840649040 is a wasteful number, since it uses less digits than its factorization.

840649040 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 841 (or 835 counting only the distinct ones).

The product of its (nonzero) digits is 27648, while the sum is 35.

The square root of 840649040 is about 28993.9483340921. The cubic root of 840649040 is about 943.7817471595.

The spelling of 840649040 in words is "eight hundred forty million, six hundred forty-nine thousand, forty".