66560400 has 120 divisors (see below), whose sum is σ = 236944160. Its totient is φ = 17746560.

The previous prime is 66560369. The next prime is 66560407. The reversal of 66560400 is 406566.

66560400 is a `hidden beast` number, since 6 + 656 + 0 + 4 + 0 + 0 = 666.

It is a tau number, because it is divible by the number of its divisors (120).

It is a Harshad number since it is a multiple of its sum of digits (27).

It is not an unprimeable number, because it can be changed into a prime (66560407) 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, 7719 + ... + 13881.

Almost surely, 2^66560400 is an apocalyptic number.

66560400 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 66560400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (118472080).

66560400 is an abundant number, since it is smaller than the sum of its proper divisors (170383760).

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

66560400 is a wasteful number, since it uses less digits than its factorization.

66560400 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6190 (or 6173 counting only the distinct ones).

The product of its (nonzero) digits is 4320, while the sum is 27.

The square root of 66560400 is about 8158.4557362285. The cubic root of 66560400 is about 405.2645733529.

Adding to 66560400 its reverse (406566), we get a palindrome (66966966).

The spelling of 66560400 in words is "sixty-six million, five hundred sixty thousand, four hundred".