84218881 has 2 divisors, whose sum is σ = 84218882. Its totient is φ = 84218880.

The previous prime is 84218873. The next prime is 84218899. The reversal of 84218881 is 18881248.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 46457856 + 37761025 = 6816^2 + 6145^2 .

It is a cyclic number.

It is not a de Polignac number, because 84218881 - 2³ = 84218873 is a prime.

It is a super-2 number, since 2×84218881² = 14185639833784322, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (84218861) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 42109440 + 42109441.

It is an arithmetic number, because the mean of its divisors is an integer number (42109441).

Almost surely, 2^84218881 is an apocalyptic number.

It is an amenable number.

84218881 is a deficient number, since it is larger than the sum of its proper divisors (1).

84218881 is an equidigital number, since it uses as much as digits as its factorization.

84218881 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 32768, while the sum is 40.

The square root of 84218881 is about 9177.0845588346. The cubic root of 84218881 is about 438.3319783226.

The spelling of 84218881 in words is "eighty-four million, two hundred eighteen thousand, eight hundred eighty-one".