84821894866 has 4 divisors (see below), whose sum is σ = 127232842302. Its totient is φ = 42410947432.

The previous prime is 84821894863. The next prime is 84821894869. The reversal of 84821894866 is 66849812848.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is an interprime number because it is at equal distance from previous prime (84821894863) and next prime (84821894869).

It can be written as a sum of positive squares in only one way, i.e., 83911605625 + 910289241 = 289675^2 + 30171^2 .

It is a junction number, because it is equal to n+sod(n) for n = 84821894798 and 84821894807.

It is not an unprimeable number, because it can be changed into a prime (84821894863) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 21205473715 + ... + 21205473718.

Almost surely, 2^84821894866 is an apocalyptic number.

84821894866 is a deficient number, since it is larger than the sum of its proper divisors (42410947436).

84821894866 is a wasteful number, since it uses less digits than its factorization.

84821894866 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 42410947435.

The product of its digits is 42467328, while the sum is 64.

The spelling of 84821894866 in words is "eighty-four billion, eight hundred twenty-one million, eight hundred ninety-four thousand, eight hundred sixty-six".