665043428 has 48 divisors (see below), whose sum is σ = 1380220800. Its totient is φ = 274337280.

The previous prime is 665043427. The next prime is 665043433. The reversal of 665043428 is 824340566.

665043428 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a super-2 number, since 2×665043428² = 884565522251982368, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 665043391 and 665043400.

It is not an unprimeable number, because it can be changed into a prime (665043427) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 306668 + ... + 308828.

It is an arithmetic number, because the mean of its divisors is an integer number (28754600).

Almost surely, 2^665043428 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 665043428, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (690110400).

665043428 is an abundant number, since it is smaller than the sum of its proper divisors (715177372).

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

665043428 is a wasteful number, since it uses less digits than its factorization.

665043428 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2580 (or 2578 counting only the distinct ones).

The product of its (nonzero) digits is 138240, while the sum is 38.

The square root of 665043428 is about 25788.4359355119. The cubic root of 665043428 is about 872.8708737121.

The spelling of 665043428 in words is "six hundred sixty-five million, forty-three thousand, four hundred twenty-eight".