84242981 has 2 divisors, whose sum is σ = 84242982. Its totient is φ = 84242980.

The previous prime is 84242971. The next prime is 84243001. The reversal of 84242981 is 18924248.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 45292900 + 38950081 = 6730^2 + 6241^2 .

It is a cyclic number.

It is not a de Polignac number, because 84242981 - 2¹⁸ = 83980837 is a prime.

It is a super-2 number, since 2×84242981² = 14193759695532722, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (84242971) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 42121490 + 42121491.

It is an arithmetic number, because the mean of its divisors is an integer number (42121491).

Almost surely, 2^84242981 is an apocalyptic number.

It is an amenable number.

84242981 is a deficient number, since it is larger than the sum of its proper divisors (1).

84242981 is an equidigital number, since it uses as much as digits as its factorization.

84242981 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 36864, while the sum is 38.

The square root of 84242981 is about 9178.3975180856. The cubic root of 84242981 is about 438.3737852313.

The spelling of 84242981 in words is "eighty-four million, two hundred forty-two thousand, nine hundred eighty-one".