66986400 has 288 divisors, whose sum is σ = 249359040. Its totient is φ = 15482880.

The previous prime is 66986371. The next prime is 66986407. The reversal of 66986400 is 468966.

66986400 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a super-3 number, since 3×66986400³ (a number of 24 digits) contains 333 as substring.

It is a Harshad number since it is a multiple of its sum of digits (39).

It is not an unprimeable number, because it can be changed into a prime (66986407) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 592744 + ... + 592856.

It is an arithmetic number, because the mean of its divisors is an integer number (865830).

Almost surely, 2^66986400 is an apocalyptic number.

66986400 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 66986400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (124679520).

66986400 is an abundant number, since it is smaller than the sum of its proper divisors (182372640).

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

66986400 is a wasteful number, since it uses less digits than its factorization.

66986400 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 168 (or 155 counting only the distinct ones).

The product of its (nonzero) digits is 62208, while the sum is 39.

The square root of 66986400 is about 8184.5219774890. The cubic root of 66986400 is about 406.1273270635.

The spelling of 66986400 in words is "sixty-six million, nine hundred eighty-six thousand, four hundred".