66633255657 has 12 divisors (see below), whose sum is σ = 96251909364. Its totient is φ = 44420382720.

The previous prime is 66633255599. The next prime is 66633255779. The reversal of 66633255657 is 75655233666.

It can be written as a sum of positive squares in 2 ways, for example, as 14680714896 + 51952540761 = 121164^2 + 227931^2 .

It is not a de Polignac number, because 66633255657 - 2⁷ = 66633255529 is a prime.

It is a super-2 number, since 2×66633255657² (a number of 22 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (66633253657) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 110953 + ... + 381545.

It is an arithmetic number, because the mean of its divisors is an integer number (8020992447).

Almost surely, 2^66633255657 is an apocalyptic number.

It is an amenable number.

66633255657 is a deficient number, since it is larger than the sum of its proper divisors (29618653707).

66633255657 is a wasteful number, since it uses less digits than its factorization.

66633255657 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 297960 (or 297957 counting only the distinct ones).

The product of its digits is 20412000, while the sum is 54.

The spelling of 66633255657 in words is "sixty-six billion, six hundred thirty-three million, two hundred fifty-five thousand, six hundred fifty-seven".