66206540 has 24 divisors (see below), whose sum is σ = 141659280. Its totient is φ = 25982528.

The previous prime is 66206531. The next prime is 66206599. The reversal of 66206540 is 4560266.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 30170 + ... + 32289.

It is an arithmetic number, because the mean of its divisors is an integer number (5902470).

Almost surely, 2^66206540 is an apocalyptic number.

It is an amenable number.

66206540 is an abundant number, since it is smaller than the sum of its proper divisors (75452740).

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

66206540 is a wasteful number, since it uses less digits than its factorization.

66206540 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 62521 (or 62519 counting only the distinct ones).

The product of its (nonzero) digits is 8640, while the sum is 29.

The square root of 66206540 is about 8136.7401334933. The cubic root of 66206540 is about 404.5451174895.

The spelling of 66206540 in words is "sixty-six million, two hundred six thousand, five hundred forty".