665620536 has 64 divisors (see below), whose sum is σ = 1934035200. Its totient is φ = 186951168.

The previous prime is 665620517. The next prime is 665620537. The reversal of 665620536 is 635026566.

It is a junction number, because it is equal to n+sod(n) for n = 665620494 and 665620503.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (665620537) by changing a digit.

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, 23665 + ... + 43488.

It is an arithmetic number, because the mean of its divisors is an integer number (30219300).

Almost surely, 2^665620536 is an apocalyptic number.

It is an amenable number.

665620536 is an abundant number, since it is smaller than the sum of its proper divisors (1268414664).

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

665620536 is a wasteful number, since it uses less digits than its factorization.

665620536 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 67228 (or 67224 counting only the distinct ones).

The product of its (nonzero) digits is 194400, while the sum is 39.

The square root of 665620536 is about 25799.6227879401. The cubic root of 665620536 is about 873.1232858614.

The spelling of 665620536 in words is "six hundred sixty-five million, six hundred twenty thousand, five hundred thirty-six".