665913828 has 24 divisors (see below), whose sum is σ = 1575685440. Its totient is φ = 218844640.

The previous prime is 665913823. The next prime is 665913869. The reversal of 665913828 is 828319566.

It is a happy number.

It is a super-2 number, since 2×665913828² = 886882452643227168, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (665913823) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 389943 + ... + 391646.

It is an arithmetic number, because the mean of its divisors is an integer number (65653560).

Almost surely, 2^665913828 is an apocalyptic number.

It is an amenable number.

665913828 is an abundant number, since it is smaller than the sum of its proper divisors (909771612).

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

665913828 is a wasteful number, since it uses less digits than its factorization.

665913828 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 781667 (or 781665 counting only the distinct ones).

The product of its digits is 622080, while the sum is 48.

The square root of 665913828 is about 25805.3061985321. The cubic root of 665913828 is about 873.2515083035.

The spelling of 665913828 in words is "six hundred sixty-five million, nine hundred thirteen thousand, eight hundred twenty-eight".