655778920 has 64 divisors (see below), whose sum is σ = 1559160000. Its totient is φ = 247546368.

The previous prime is 655778917. The next prime is 655778947. The reversal of 655778920 is 29877556.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 213556 + ... + 216604.

It is an arithmetic number, because the mean of its divisors is an integer number (24361875).

Almost surely, 2^655778920 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 655778920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (779580000).

655778920 is an abundant number, since it is smaller than the sum of its proper divisors (903381080).

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

655778920 is a wasteful number, since it uses less digits than its factorization.

655778920 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3362 (or 3358 counting only the distinct ones).

The product of its (nonzero) digits is 1058400, while the sum is 49.

The square root of 655778920 is about 25608.1807241358. The cubic root of 655778920 is about 868.7986766370.

The spelling of 655778920 in words is "six hundred fifty-five million, seven hundred seventy-eight thousand, nine hundred twenty".