66061600 has 72 divisors (see below), whose sum is σ = 175957488. Its totient is φ = 24019200.

The previous prime is 66061591. The next prime is 66061601. The reversal of 66061600 is 616066.

It is a Harshad number since it is a multiple of its sum of digits (25).

It is not an unprimeable number, because it can be changed into a prime (66061601) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 5047 + ... + 12553.

It is an arithmetic number, because the mean of its divisors is an integer number (2443854).

Almost surely, 2^66061600 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 66061600, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (87978744).

66061600 is an abundant number, since it is smaller than the sum of its proper divisors (109895888).

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

66061600 is a wasteful number, since it uses less digits than its factorization.

66061600 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7538 (or 7525 counting only the distinct ones).

The product of its (nonzero) digits is 1296, while the sum is 25.

The square root of 66061600 is about 8127.8287383532. The cubic root of 66061600 is about 404.2496904346.

Adding to 66061600 its reverse (616066), we get a palindrome (66677666).

It can be divided in two parts, 6 and 6061600, that added together give a palindrome (6061606).

The spelling of 66061600 in words is "sixty-six million, sixty-one thousand, six hundred".