66600551 has 4 divisors (see below), whose sum is σ = 68017632. Its totient is φ = 65183472.

The previous prime is 66600539. The next prime is 66600563. The reversal of 66600551 is 15500666.

It is a semiprime because it is the product of two primes.

It is an interprime number because it is at equal distance from previous prime (66600539) and next prime (66600563).

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-66600551 is a prime.

It is a Duffinian number.

It is a zygodrome in base 2.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66600581) 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 3 ways as a sum of consecutive naturals, for example, 708470 + ... + 708563.

It is an arithmetic number, because the mean of its divisors is an integer number (17004408).

Almost surely, 2^66600551 is an apocalyptic number.

66600551 is a deficient number, since it is larger than the sum of its proper divisors (1417081).

66600551 is a wasteful number, since it uses less digits than its factorization.

66600551 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1417080.

The product of its (nonzero) digits is 5400, while the sum is 29.

The square root of 66600551 is about 8160.9160637762. The cubic root of 66600551 is about 405.3460457555.

The spelling of 66600551 in words is "sixty-six million, six hundred thousand, five hundred fifty-one".