85681999668 has 12 divisors (see below), whose sum is σ = 199924665920. Its totient is φ = 28560666552.

The previous prime is 85681999657. The next prime is 85681999691. The reversal of 85681999668 is 86699918658.

It is a tau number, because it is divible by the number of its divisors (12).

It is a super-2 number, since 2×85681999668² (a number of 23 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 85681999668.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3570083308 + ... + 3570083331.

Almost surely, 2^85681999668 is an apocalyptic number.

It is an amenable number.

85681999668 is an abundant number, since it is smaller than the sum of its proper divisors (114242666252).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

85681999668 is a wasteful number, since it uses less digits than its factorization.

85681999668 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7140166646 (or 7140166644 counting only the distinct ones).

The product of its digits is 403107840, while the sum is 75.

The spelling of 85681999668 in words is "eighty-five billion, six hundred eighty-one million, nine hundred ninety-nine thousand, six hundred sixty-eight".