66557005 has 8 divisors (see below), whose sum is σ = 79925400. Its totient is φ = 53207616.

The previous prime is 66556999. The next prime is 66557011. The reversal of 66557005 is 50075566.

It is an interprime number because it is at equal distance from previous prime (66556999) and next prime (66557011).

It can be written as a sum of positive squares in 4 ways, for example, as 2604996 + 63952009 = 1614^2 + 7997^2 .

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

It is a cyclic number.

It is not a de Polignac number, because 66557005 - 2⁷ = 66556877 is a prime.

It is a congruent 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, 4651 + ... + 12439.

It is an arithmetic number, because the mean of its divisors is an integer number (9990675).

Almost surely, 2^66557005 is an apocalyptic number.

It is an amenable number.

66557005 is a deficient number, since it is larger than the sum of its proper divisors (13368395).

66557005 is a wasteful number, since it uses less digits than its factorization.

66557005 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9503.

The product of its (nonzero) digits is 31500, while the sum is 34.

The square root of 66557005 is about 8158.2476672384. The cubic root of 66557005 is about 405.2576828864.

The spelling of 66557005 in words is "sixty-six million, five hundred fifty-seven thousand, five".