66512440 has 32 divisors (see below), whose sum is σ = 150842880. Its totient is φ = 26393472.

The previous prime is 66512431. The next prime is 66512447. The reversal of 66512440 is 4421566.

It is a junction number, because it is equal to n+sod(n) for n = 66512399 and 66512408.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66512447) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1467 + ... + 11626.

It is an arithmetic number, because the mean of its divisors is an integer number (4713840).

Almost surely, 2^66512440 is an apocalyptic number.

It is an amenable number.

66512440 is an abundant number, since it is smaller than the sum of its proper divisors (84330440).

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

66512440 is a wasteful number, since it uses less digits than its factorization.

66512440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13231 (or 13227 counting only the distinct ones).

The product of its (nonzero) digits is 5760, while the sum is 28.

The square root of 66512440 is about 8155.5159248205. The cubic root of 66512440 is about 405.1672123639.

The spelling of 66512440 in words is "sixty-six million, five hundred twelve thousand, four hundred forty".