1647878040 has 128 divisors (see below), whose sum is σ = 5501836800. Its totient is φ = 438721920.

The previous prime is 1647878009. The next prime is 1647878041. The reversal of 1647878040 is 408787461.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1647878041) 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, 1264029 + ... + 1265331.

It is an arithmetic number, because the mean of its divisors is an integer number (42983100).

Almost surely, 2^1647878040 is an apocalyptic number.

1647878040 is a gapful number since it is divisible by the number (10) 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 1647878040, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2750918400).

1647878040 is an abundant number, since it is smaller than the sum of its proper divisors (3853958760).

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

1647878040 is a wasteful number, since it uses less digits than its factorization.

1647878040 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2494 (or 2484 counting only the distinct ones).

The product of its (nonzero) digits is 301056, while the sum is 45.

The square root of 1647878040 is about 40594.0640980920. The cubic root of 1647878040 is about 1181.1589781212.

The spelling of 1647878040 in words is "one billion, six hundred forty-seven million, eight hundred seventy-eight thousand, forty".