66243554 has 16 divisors (see below), whose sum is σ = 108366720. Its totient is φ = 30186000.

The previous prime is 66243553. The next prime is 66243563. The reversal of 66243554 is 45534266.

It is a happy number.

It is a Smith number, since the sum of its digits (35) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is not an unprimeable number, because it can be changed into a prime (66243553) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 14072 + ... + 18179.

It is an arithmetic number, because the mean of its divisors is an integer number (6772920).

Almost surely, 2^66243554 is an apocalyptic number.

66243554 is a deficient number, since it is larger than the sum of its proper divisors (42123166).

66243554 is a wasteful number, since it uses less digits than its factorization.

66243554 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 32345.

The product of its digits is 86400, while the sum is 35.

The square root of 66243554 is about 8139.0143137852. The cubic root of 66243554 is about 404.6204929402.

The spelling of 66243554 in words is "sixty-six million, two hundred forty-three thousand, five hundred fifty-four".