66361605657 has 8 divisors (see below), whose sum is σ = 88692313920. Its totient is φ = 44135983920.

The previous prime is 66361605649. The next prime is 66361605749. The reversal of 66361605657 is 75650616366.

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

It is not a de Polignac number, because 66361605657 - 2³ = 66361605649 is a prime.

It is not an unprimeable number, because it can be changed into a prime (66361605257) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 26270157 + ... + 26272682.

It is an arithmetic number, because the mean of its divisors is an integer number (11086539240).

Almost surely, 2^66361605657 is an apocalyptic number.

It is an amenable number.

66361605657 is a deficient number, since it is larger than the sum of its proper divisors (22330708263).

66361605657 is a wasteful number, since it uses less digits than its factorization.

66361605657 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 52543263.

The product of its (nonzero) digits is 4082400, while the sum is 51.

The spelling of 66361605657 in words is "sixty-six billion, three hundred sixty-one million, six hundred five thousand, six hundred fifty-seven".