66561141 has 4 divisors (see below), whose sum is σ = 88748192. Its totient is φ = 44374092.

The previous prime is 66561133. The next prime is 66561197. The reversal of 66561141 is 14116566.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 66561141 - 2³ = 66561133 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 66561099 and 66561108.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66561101) 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, 11093521 + ... + 11093526.

It is an arithmetic number, because the mean of its divisors is an integer number (22187048).

Almost surely, 2^66561141 is an apocalyptic number.

It is an amenable number.

66561141 is a deficient number, since it is larger than the sum of its proper divisors (22187051).

66561141 is a wasteful number, since it uses less digits than its factorization.

66561141 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 22187050.

The product of its digits is 4320, while the sum is 30.

The square root of 66561141 is about 8158.5011491082. The cubic root of 66561141 is about 405.2660772498.

The spelling of 66561141 in words is "sixty-six million, five hundred sixty-one thousand, one hundred forty-one".