66505550601 has 32 divisors (see below), whose sum is σ = 102543524608. Its totient is φ = 37553725440.

The previous prime is 66505550591. The next prime is 66505550677. The reversal of 66505550601 is 10605550566.

It is not a de Polignac number, because 66505550601 - 2⁶ = 66505550537 is a prime.

It is a super-2 number, since 2×66505550601² (a number of 22 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 66505550601.

It is not an unprimeable number, because it can be changed into a prime (66505550701) 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 31 ways as a sum of consecutive naturals, for example, 1321761 + ... + 1371153.

It is an arithmetic number, because the mean of its divisors is an integer number (3204485144).

Almost surely, 2^66505550601 is an apocalyptic number.

It is an amenable number.

66505550601 is a deficient number, since it is larger than the sum of its proper divisors (36037974007).

66505550601 is a wasteful number, since it uses less digits than its factorization.

66505550601 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 50161.

The product of its (nonzero) digits is 135000, while the sum is 39.

The spelling of 66505550601 in words is "sixty-six billion, five hundred five million, five hundred fifty thousand, six hundred one".