85642806866 has 4 divisors (see below), whose sum is σ = 128464210302. Its totient is φ = 42821403432.

The previous prime is 85642806863. The next prime is 85642806889. The reversal of 85642806866 is 66860824658.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 66860824658 = 2 ⋅33430412329.

It can be written as a sum of positive squares in only one way, i.e., 85576726225 + 66080641 = 292535^2 + 8129^2 .

It is not an unprimeable number, because it can be changed into a prime (85642806863) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 21410701715 + ... + 21410701718.

Almost surely, 2^85642806866 is an apocalyptic number.

85642806866 is a deficient number, since it is larger than the sum of its proper divisors (42821403436).

85642806866 is a wasteful number, since it uses less digits than its factorization.

85642806866 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 42821403435.

The product of its (nonzero) digits is 26542080, while the sum is 59.

The spelling of 85642806866 in words is "eighty-five billion, six hundred forty-two million, eight hundred six thousand, eight hundred sixty-six".