66516410 has 16 divisors (see below), whose sum is σ = 126772776. Its totient is φ = 25041408.

The previous prime is 66516409. The next prime is 66516419. The reversal of 66516410 is 1461566.

It can be written as a sum of positive squares in 4 ways, for example, as 64818601 + 1697809 = 8051^2 + 1303^2 .

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (66516419) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 195467 + ... + 195806.

Almost surely, 2^66516410 is an apocalyptic number.

66516410 is a deficient number, since it is larger than the sum of its proper divisors (60256366).

66516410 is a wasteful number, since it uses less digits than its factorization.

66516410 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 391297.

The product of its (nonzero) digits is 4320, while the sum is 29.

The square root of 66516410 is about 8155.7593147419. The cubic root of 66516410 is about 405.1752734215.

Adding to 66516410 its reverse (1461566), we get a palindrome (67977976).

The spelling of 66516410 in words is "sixty-six million, five hundred sixteen thousand, four hundred ten".