66501957606 has 64 divisors (see below), whose sum is σ = 155810704896. Its totient is φ = 18525369600.

The previous prime is 66501957559. The next prime is 66501957607. The reversal of 66501957606 is 60675910566.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66501957607) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 2903941 + ... + 2926751.

It is an arithmetic number, because the mean of its divisors is an integer number (2434542264).

Almost surely, 2^66501957606 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 66501957606, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (77905352448).

66501957606 is an abundant number, since it is smaller than the sum of its proper divisors (89308747290).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

66501957606 is a wasteful number, since it uses less digits than its factorization.

66501957606 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 24557.

The product of its (nonzero) digits is 2041200, while the sum is 51.

The spelling of 66501957606 in words is "sixty-six billion, five hundred one million, nine hundred fifty-seven thousand, six hundred six".