84215291 has 2 divisors, whose sum is σ = 84215292. Its totient is φ = 84215290.

The previous prime is 84215249. The next prime is 84215309. The reversal of 84215291 is 19251248.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 84215291 - 2⁶ = 84215227 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (84215491) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 42107645 + 42107646.

It is an arithmetic number, because the mean of its divisors is an integer number (42107646).

Almost surely, 2^84215291 is an apocalyptic number.

84215291 is a deficient number, since it is larger than the sum of its proper divisors (1).

84215291 is an equidigital number, since it uses as much as digits as its factorization.

84215291 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 5760, while the sum is 32.

The square root of 84215291 is about 9176.8889608625. Note that the first 3 decimals coincide. The cubic root of 84215291 is about 438.3257499720.

The spelling of 84215291 in words is "eighty-four million, two hundred fifteen thousand, two hundred ninety-one".