66406550 has 24 divisors (see below), whose sum is σ = 141162096. Its totient is φ = 22767840.

The previous prime is 66406541. The next prime is 66406583. The reversal of 66406550 is 5560466.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 94517 + ... + 95216.

It is an arithmetic number, because the mean of its divisors is an integer number (5881754).

Almost surely, 2^66406550 is an apocalyptic number.

66406550 is an abundant number, since it is smaller than the sum of its proper divisors (74755546).

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

66406550 is a wasteful number, since it uses less digits than its factorization.

66406550 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 189752 (or 189747 counting only the distinct ones).

The product of its (nonzero) digits is 21600, while the sum is 32.

The square root of 66406550 is about 8149.0214136423. The cubic root of 66406550 is about 404.9520849680.

The spelling of 66406550 in words is "sixty-six million, four hundred six thousand, five hundred fifty".