665615028 has 48 divisors (see below), whose sum is σ = 1675157120. Its totient is φ = 204488064.

The previous prime is 665615023. The next prime is 665615057. The reversal of 665615028 is 820516566.

It is a Harshad number since it is a multiple of its sum of digits (39).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (665615023) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 110478 + ... + 116346.

Almost surely, 2^665615028 is an apocalyptic number.

It is an amenable number.

665615028 is an abundant number, since it is smaller than the sum of its proper divisors (1009542092).

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

665615028 is a wasteful number, since it uses less digits than its factorization.

665615028 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6616 (or 6614 counting only the distinct ones).

The product of its (nonzero) digits is 86400, while the sum is 39.

The square root of 665615028 is about 25799.5160419726. The cubic root of 665615028 is about 873.1208774941.

The spelling of 665615028 in words is "six hundred sixty-five million, six hundred fifteen thousand, twenty-eight".