84509805 has 32 divisors (see below), whose sum is σ = 144039168. Its totient is φ = 42163200.

The previous prime is 84509801. The next prime is 84509851. The reversal of 84509805 is 50890548.

It is not a de Polignac number, because 84509805 - 2² = 84509801 is a prime.

It is a super-2 number, since 2×84509805² = 14283814282276050, which contains 22 as substring.

It is a Smith number, since the sum of its digits (39) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (84509801) 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 in 31 ways as a sum of consecutive naturals, for example, 45240 + ... + 47070.

It is an arithmetic number, because the mean of its divisors is an integer number (4501224).

Almost surely, 2^84509805 is an apocalyptic number.

84509805 is a gapful number since it is divisible by the number (85) formed by its first and last digit.

It is an amenable number.

84509805 is a deficient number, since it is larger than the sum of its proper divisors (59529363).

84509805 is a wasteful number, since it uses less digits than its factorization.

84509805 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2037.

The product of its (nonzero) digits is 57600, while the sum is 39.

The square root of 84509805 is about 9192.9214616465. The cubic root of 84509805 is about 438.8361199769.

The spelling of 84509805 in words is "eighty-four million, five hundred nine thousand, eight hundred five".