66610400 has 72 divisors (see below), whose sum is σ = 165786264. Its totient is φ = 26124800.

The previous prime is 66610381. The next prime is 66610417. The reversal of 66610400 is 401666.

66610400 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a congruent number.

It is an unprimeable number.

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 11 ways as a sum of consecutive naturals, for example, 41615 + ... + 43185.

It is an arithmetic number, because the mean of its divisors is an integer number (2302587).

Almost surely, 2^66610400 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 66610400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (82893132).

66610400 is an abundant number, since it is smaller than the sum of its proper divisors (99175864).

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

66610400 is a wasteful number, since it uses less digits than its factorization.

66610400 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1644 (or 1631 counting only the distinct ones).

The product of its (nonzero) digits is 864, while the sum is 23.

The square root of 66610400 is about 8161.5194663739. The cubic root of 66610400 is about 405.3660258526.

The spelling of 66610400 in words is "sixty-six million, six hundred ten thousand, four hundred".