66601655 has 16 divisors (see below), whose sum is σ = 82301184. Its totient is φ = 51717120.

The previous prime is 66601649. The next prime is 66601657. The reversal of 66601655 is 55610666.

It is not a de Polignac number, because 66601655 - 2¹⁰ = 66600631 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66601657) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 24410 + ... + 27000.

It is an arithmetic number, because the mean of its divisors is an integer number (5143824).

Almost surely, 2^66601655 is an apocalyptic number.

66601655 is a deficient number, since it is larger than the sum of its proper divisors (15699529).

66601655 is a wasteful number, since it uses less digits than its factorization.

66601655 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2746.

The product of its (nonzero) digits is 32400, while the sum is 35.

The square root of 66601655 is about 8160.9837029613. The cubic root of 66601655 is about 405.3482854745.

The spelling of 66601655 in words is "sixty-six million, six hundred one thousand, six hundred fifty-five".