66501620099 has 2 divisors, whose sum is σ = 66501620100. Its totient is φ = 66501620098.

The previous prime is 66501620063. The next prime is 66501620113. The reversal of 66501620099 is 99002610566.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 66501620099 - 2²⁸ = 66233184643 is a prime.

It is not a weakly prime, because it can be changed into another prime (66501623099) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33250810049 + 33250810050.

It is an arithmetic number, because the mean of its divisors is an integer number (33250810050).

Almost surely, 2^66501620099 is an apocalyptic number.

66501620099 is a deficient number, since it is larger than the sum of its proper divisors (1).

66501620099 is an equidigital number, since it uses as much as digits as its factorization.

66501620099 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 174960, while the sum is 44.

The spelling of 66501620099 in words is "sixty-six billion, five hundred one million, six hundred twenty thousand, ninety-nine".