66299239681 has 8 divisors (see below), whose sum is σ = 68572396800. Its totient is φ = 64034487120.

The previous prime is 66299239661. The next prime is 66299239733. The reversal of 66299239681 is 18693299266.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 66299239681 - 2¹¹ = 66299237633 is a prime.

It is a super-2 number, since 2×66299239681² (a number of 22 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (66299239631) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2085091 + ... + 2116648.

It is an arithmetic number, because the mean of its divisors is an integer number (8571549600).

Almost surely, 2^66299239681 is an apocalyptic number.

It is an amenable number.

66299239681 is a deficient number, since it is larger than the sum of its proper divisors (2273157119).

66299239681 is a wasteful number, since it uses less digits than its factorization.

66299239681 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4202279.

The product of its digits is 15116544, while the sum is 61.

The spelling of 66299239681 in words is "sixty-six billion, two hundred ninety-nine million, two hundred thirty-nine thousand, six hundred eighty-one".