505665720 has 256 divisors, whose sum is σ = 1941580800. Its totient is φ = 114670080.

The previous prime is 505665709. The next prime is 505665773. The reversal of 505665720 is 27566505.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 1595002 + ... + 1595318.

It is an arithmetic number, because the mean of its divisors is an integer number (7584300).

Almost surely, 2^505665720 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 505665720, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (970790400).

505665720 is an abundant number, since it is smaller than the sum of its proper divisors (1435915080).

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

505665720 is a wasteful number, since it uses less digits than its factorization.

505665720 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 555 (or 545 counting only the distinct ones).

The product of its (nonzero) digits is 63000, while the sum is 36.

The square root of 505665720 is about 22487.0122515198. The cubic root of 505665720 is about 796.6871964349.

The spelling of 505665720 in words is "five hundred five million, six hundred sixty-five thousand, seven hundred twenty".