66143505 has 16 divisors (see below), whose sum is σ = 106665984. Its totient is φ = 34997760.

The previous prime is 66143501. The next prime is 66143507. The reversal of 66143505 is 50534166.

It is not a de Polignac number, because 66143505 - 2² = 66143501 is a prime.

It is not an unprimeable number, because it can be changed into a prime (66143501) 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, 15456 + ... + 19265.

It is an arithmetic number, because the mean of its divisors is an integer number (6666624).

Almost surely, 2^66143505 is an apocalyptic number.

It is an amenable number.

66143505 is a deficient number, since it is larger than the sum of its proper divisors (40522479).

66143505 is a wasteful number, since it uses less digits than its factorization.

66143505 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 34856.

The product of its (nonzero) digits is 10800, while the sum is 30.

The square root of 66143505 is about 8132.8657310938. The cubic root of 66143505 is about 404.4166880889.

The spelling of 66143505 in words is "sixty-six million, one hundred forty-three thousand, five hundred five".