655823840 has 144 divisors (see below), whose sum is σ = 1881224352. Its totient is φ = 215018496.

The previous prime is 655823837. The next prime is 655823849. The reversal of 655823840 is 48328556.

It is a super-2 number, since 2×655823840² = 860209818224691200, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (655823849) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 178502 + ... + 182138.

It is an arithmetic number, because the mean of its divisors is an integer number (13064058).

Almost surely, 2^655823840 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 655823840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (940612176).

655823840 is an abundant number, since it is smaller than the sum of its proper divisors (1225400512).

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

655823840 is a wasteful number, since it uses less digits than its factorization.

655823840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3689 (or 3674 counting only the distinct ones).

The product of its (nonzero) digits is 230400, while the sum is 41.

The square root of 655823840 is about 25609.0577725929. The cubic root of 655823840 is about 868.8185133758.

The spelling of 655823840 in words is "six hundred fifty-five million, eight hundred twenty-three thousand, eight hundred forty".