66558101 has 2 divisors, whose sum is σ = 66558102. Its totient is φ = 66558100.

The previous prime is 66558071. The next prime is 66558119. The reversal of 66558101 is 10185566.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 61999876 + 4558225 = 7874^2 + 2135^2 .

It is a cyclic number.

It is not a de Polignac number, because 66558101 - 2²² = 62363797 is a prime.

It is a super-3 number, since 3×66558101³ (a number of 24 digits) contains 333 as substring.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (66558131) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33279050 + 33279051.

It is an arithmetic number, because the mean of its divisors is an integer number (33279051).

Almost surely, 2^66558101 is an apocalyptic number.

It is an amenable number.

66558101 is a deficient number, since it is larger than the sum of its proper divisors (1).

66558101 is an equidigital number, since it uses as much as digits as its factorization.

66558101 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 7200, while the sum is 32.

The square root of 66558101 is about 8158.3148382494. The cubic root of 66558101 is about 405.2599073454.

The spelling of 66558101 in words is "sixty-six million, five hundred fifty-eight thousand, one hundred one".