66901 has 4 divisors (see below), whose sum is σ = 67500. Its totient is φ = 66304.

The previous prime is 66889. The next prime is 66919. The reversal of 66901 is 10966.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length, and also an emirpimes, since its reverse is a distinct semiprime: 10966 = 2 ⋅5483.

It can be written as a sum of positive squares in 2 ways, for example, as 22801 + 44100 = 151^2 + 210^2 .

It is a cyclic number.

It is not a de Polignac number, because 66901 - 2¹¹ = 64853 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 (66931) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 76 + ... + 373.

It is an arithmetic number, because the mean of its divisors is an integer number (16875).

2⁶⁶⁹⁰¹ is an apocalyptic number.

It is an amenable number.

66901 is a deficient number, since it is larger than the sum of its proper divisors (599).

66901 is a wasteful number, since it uses less digits than its factorization.

66901 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 598.

The product of its (nonzero) digits is 324, while the sum is 22.

The square root of 66901 is about 258.6522762320. The cubic root of 66901 is about 40.5954665034.

The spelling of 66901 in words is "sixty-six thousand, nine hundred one".