84821894869 has 2 divisors, whose sum is σ = 84821894870. Its totient is φ = 84821894868.

The previous prime is 84821894863. The next prime is 84821894881. The reversal of 84821894869 is 96849812848.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 79940776644 + 4881118225 = 282738^2 + 69865^2 .

It is a cyclic number.

It is not a de Polignac number, because 84821894869 - 2⁹ = 84821894357 is a prime.

It is a super-2 number, since 2×84821894869² (a number of 23 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (84821894863) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 42410947434 + 42410947435.

It is an arithmetic number, because the mean of its divisors is an integer number (42410947435).

Almost surely, 2^84821894869 is an apocalyptic number.

It is an amenable number.

84821894869 is a deficient number, since it is larger than the sum of its proper divisors (1).

84821894869 is an equidigital number, since it uses as much as digits as its factorization.

84821894869 is an evil number, because the sum of its binary digits is even.

The product of its digits is 63700992, while the sum is 67.

The spelling of 84821894869 in words is "eighty-four billion, eight hundred twenty-one million, eight hundred ninety-four thousand, eight hundred sixty-nine".