66125608199 has 4 divisors (see below), whose sum is σ = 75572123664. Its totient is φ = 56679092736.

The previous prime is 66125608147. The next prime is 66125608217. The reversal of 66125608199 is 99180652166.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 99180652166 = 2 ⋅49590326083.

It is not a de Polignac number, because 66125608199 - 2¹⁶ = 66125542663 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 66125608199.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66125608699) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4723257722 + ... + 4723257735.

It is an arithmetic number, because the mean of its divisors is an integer number (18893030916).

Almost surely, 2^66125608199 is an apocalyptic number.

66125608199 is a deficient number, since it is larger than the sum of its proper divisors (9446515465).

66125608199 is an equidigital number, since it uses as much as digits as its factorization.

66125608199 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9446515464.

The product of its (nonzero) digits is 1399680, while the sum is 53.

The spelling of 66125608199 in words is "sixty-six billion, one hundred twenty-five million, six hundred eight thousand, one hundred ninety-nine".