66205554 has 16 divisors (see below), whose sum is σ = 132671520. Its totient is φ = 22025120.

The previous prime is 66205541. The next prime is 66205591. The reversal of 66205554 is 45550266.

It is a happy number.

It is a Smith number, since the sum of its digits (33) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 7464 + ... + 13715.

It is an arithmetic number, because the mean of its divisors is an integer number (8291970).

Almost surely, 2^66205554 is an apocalyptic number.

66205554 is an abundant number, since it is smaller than the sum of its proper divisors (66465966).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

66205554 is a wasteful number, since it uses less digits than its factorization.

66205554 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21705.

The product of its (nonzero) digits is 36000, while the sum is 33.

The square root of 66205554 is about 8136.6795438926. The cubic root of 66205554 is about 404.5431092112.

The spelling of 66205554 in words is "sixty-six million, two hundred five thousand, five hundred fifty-four".