665025400 has 96 divisors (see below), whose sum is σ = 1678173840. Its totient is φ = 243624960.

The previous prime is 665025391. The next prime is 665025409. The reversal of 665025400 is 4520566.

It is an interprime number because it is at equal distance from previous prime (665025391) and next prime (665025409).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (665025409) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 355267 + ... + 357133.

Almost surely, 2^665025400 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 665025400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (839086920).

665025400 is an abundant number, since it is smaller than the sum of its proper divisors (1013148440).

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

665025400 is a wasteful number, since it uses less digits than its factorization.

665025400 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2033 (or 2024 counting only the distinct ones).

The product of its (nonzero) digits is 7200, while the sum is 28.

The square root of 665025400 is about 25788.0863966290. The cubic root of 665025400 is about 872.8629863784.

Adding to 665025400 its reverse (4520566), we get a palindrome (669545966).

The spelling of 665025400 in words is "six hundred sixty-five million, twenty-five thousand, four hundred".