665709528 has 64 divisors (see below), whose sum is σ = 1922382720. Its totient is φ = 189862400.

The previous prime is 665709523. The next prime is 665709547. The reversal of 665709528 is 825907566.

It is a happy number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (665709523) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 69678 + ... + 78653.

It is an arithmetic number, because the mean of its divisors is an integer number (30037230).

Almost surely, 2^665709528 is an apocalyptic number.

665709528 is a gapful number since it is divisible by the number (68) formed by its first and last digit.

It is an amenable number.

665709528 is an abundant number, since it is smaller than the sum of its proper divisors (1256673192).

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

665709528 is a wasteful number, since it uses less digits than its factorization.

665709528 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 148368 (or 148364 counting only the distinct ones).

The product of its (nonzero) digits is 907200, while the sum is 48.

The square root of 665709528 is about 25801.3474066763. The cubic root of 665709528 is about 873.1621956810.

The spelling of 665709528 in words is "six hundred sixty-five million, seven hundred nine thousand, five hundred twenty-eight".