66550555551 has 8 divisors (see below), whose sum is σ = 88735265920. Its totient is φ = 44366441112.

The previous prime is 66550555543. The next prime is 66550555553. The reversal of 66550555551 is 15555505566.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 66550555551 - 2³ = 66550555543 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 66550555551.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66550555553) 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, 360420 + ... + 512838.

It is an arithmetic number, because the mean of its divisors is an integer number (11091908240).

Almost surely, 2^66550555551 is an apocalyptic number.

66550555551 is a deficient number, since it is larger than the sum of its proper divisors (22184710369).

66550555551 is a wasteful number, since it uses less digits than its factorization.

66550555551 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 297965.

The product of its (nonzero) digits is 2812500, while the sum is 48.

The spelling of 66550555551 in words is "sixty-six billion, five hundred fifty million, five hundred fifty-five thousand, five hundred fifty-one".