665955408 has 80 divisors (see below), whose sum is σ = 1768743936. Its totient is φ = 215809920.

The previous prime is 665955403. The next prime is 665955413. The reversal of 665955408 is 804559566.

It is an interprime number because it is at equal distance from previous prime (665955403) and next prime (665955413).

It is a Harshad number since it is a multiple of its sum of digits (48).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (665955403) 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, 366823 + ... + 368633.

Almost surely, 2^665955408 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 665955408, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (884371968).

665955408 is an abundant number, since it is smaller than the sum of its proper divisors (1102788528).

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

665955408 is a wasteful number, since it uses less digits than its factorization.

665955408 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2032 (or 2026 counting only the distinct ones).

The product of its (nonzero) digits is 1296000, while the sum is 48.

The square root of 665955408 is about 25806.1118342148. Note that the first 3 decimals coincide. The cubic root of 665955408 is about 873.2696833488.

The spelling of 665955408 in words is "six hundred sixty-five million, nine hundred fifty-five thousand, four hundred eight".