66115500 has 96 divisors (see below), whose sum is σ = 210083328. Its totient is φ = 16024000.

The previous prime is 66115487. The next prime is 66115507. The reversal of 66115500 is 551166.

It is a zygodrome in base 10.

It is not an unprimeable number, because it can be changed into a prime (66115507) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 14497 + ... + 18503.

It is an arithmetic number, because the mean of its divisors is an integer number (2188368).

Almost surely, 2^66115500 is an apocalyptic number.

66115500 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 66115500, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (105041664).

66115500 is an abundant number, since it is smaller than the sum of its proper divisors (143967828).

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

66115500 is a wasteful number, since it uses less digits than its factorization.

66115500 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4040 (or 4028 counting only the distinct ones).

The product of its (nonzero) digits is 900, while the sum is 24.

The square root of 66115500 is about 8131.1438309748. The cubic root of 66115500 is about 404.3596036825.

Adding to 66115500 its reverse (551166), we get a palindrome (66666666).

It can be divided in two parts, 661 and 15500, that added together give a palindrome (16161).

The spelling of 66115500 in words is "sixty-six million, one hundred fifteen thousand, five hundred".