66530400 has 144 divisors (see below), whose sum is σ = 228110400. Its totient is φ = 16796160.

The previous prime is 66530389. The next prime is 66530407. The reversal of 66530400 is 403566.

It is a Harshad number since it is a multiple of its sum of digits (24).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66530407) 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, 44871 + ... + 46329.

It is an arithmetic number, because the mean of its divisors is an integer number (1584100).

Almost surely, 2^66530400 is an apocalyptic number.

66530400 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 66530400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (114055200).

66530400 is an abundant number, since it is smaller than the sum of its proper divisors (161580000).

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

66530400 is a wasteful number, since it uses less digits than its factorization.

66530400 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1501 (or 1488 counting only the distinct ones).

The product of its (nonzero) digits is 2160, while the sum is 24.

The square root of 66530400 is about 8156.6169457686. The cubic root of 66530400 is about 405.2036774635.

Adding to 66530400 its reverse (403566), we get a palindrome (66933966).

The spelling of 66530400 in words is "sixty-six million, five hundred thirty thousand, four hundred".