66839953 has 4 divisors (see below), whose sum is σ = 67186468. Its totient is φ = 66493440.

The previous prime is 66839917. The next prime is 66839959. The reversal of 66839953 is 35993866.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 43191184 + 23648769 = 6572^2 + 4863^2 .

It is a cyclic number.

It is not a de Polignac number, because 66839953 - 2²¹ = 64742801 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 66839897 and 66839906.

It is not an unprimeable number, because it can be changed into a prime (66839959) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 172968 + ... + 173353.

It is an arithmetic number, because the mean of its divisors is an integer number (16796617).

Almost surely, 2^66839953 is an apocalyptic number.

It is an amenable number.

66839953 is a deficient number, since it is larger than the sum of its proper divisors (346515).

66839953 is a wasteful number, since it uses less digits than its factorization.

66839953 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 346514.

The product of its digits is 1049760, while the sum is 49.

The square root of 66839953 is about 8175.5704999712. The cubic root of 66839953 is about 405.8311499090.

The spelling of 66839953 in words is "sixty-six million, eight hundred thirty-nine thousand, nine hundred fifty-three".