84408521 has 2 divisors, whose sum is σ = 84408522. Its totient is φ = 84408520.

The previous prime is 84408517. The next prime is 84408523. The reversal of 84408521 is 12580448.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 75342400 + 9066121 = 8680^2 + 3011^2 .

It is a cyclic number.

It is not a de Polignac number, because 84408521 - 2² = 84408517 is a prime.

Together with 84408523, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (84408523) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 42204260 + 42204261.

It is an arithmetic number, because the mean of its divisors is an integer number (42204261).

Almost surely, 2^84408521 is an apocalyptic number.

It is an amenable number.

84408521 is a deficient number, since it is larger than the sum of its proper divisors (1).

84408521 is an equidigital number, since it uses as much as digits as its factorization.

84408521 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 10240, while the sum is 32.

The square root of 84408521 is about 9187.4110063717. The cubic root of 84408521 is about 438.6607365964.

Adding to 84408521 its reverse (12580448), we get a palindrome (96988969).

It can be divided in two parts, 8440 and 8521, that added together give a palindrome (16961).

The spelling of 84408521 in words is "eighty-four million, four hundred eight thousand, five hundred twenty-one".