66650555 has 16 divisors (see below), whose sum is σ = 82982880. Its totient is φ = 51330048.

The previous prime is 66650513. The next prime is 66650593. The reversal of 66650555 is 55505666.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 66650555 - 2¹⁴ = 66634171 is a prime.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 97244 + ... + 97926.

It is an arithmetic number, because the mean of its divisors is an integer number (5186430).

Almost surely, 2^66650555 is an apocalyptic number.

66650555 is a deficient number, since it is larger than the sum of its proper divisors (16332325).

66650555 is a wasteful number, since it uses less digits than its factorization.

66650555 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1390.

The product of its (nonzero) digits is 135000, while the sum is 38.

The square root of 66650555 is about 8163.9791156029. The cubic root of 66650555 is about 405.4474656027.

The spelling of 66650555 in words is "sixty-six million, six hundred fifty thousand, five hundred fifty-five".