8643391840 has 48 divisors (see below), whose sum is σ = 21494758320. Its totient is φ = 3275389440.

The previous prime is 8643391831. The next prime is 8643391847. The reversal of 8643391840 is 481933468.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (8643391847) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1418571 + ... + 1424650.

It is an arithmetic number, because the mean of its divisors is an integer number (447807465).

Almost surely, 2^8643391840 is an apocalyptic number.

8643391840 is a gapful number since it is divisible by the number (80) formed by its first and last digit.

It is an amenable number.

8643391840 is an abundant number, since it is smaller than the sum of its proper divisors (12851366480).

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

8643391840 is a wasteful number, since it uses less digits than its factorization.

8643391840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2843255 (or 2843247 counting only the distinct ones).

The product of its (nonzero) digits is 497664, while the sum is 46.

The square root of 8643391840 is about 92969.8437128943. The cubic root of 8643391840 is about 2052.2396177717.

The spelling of 8643391840 in words is "eight billion, six hundred forty-three million, three hundred ninety-one thousand, eight hundred forty".