84644561 has 4 divisors (see below), whose sum is σ = 84667572. Its totient is φ = 84621552.

The previous prime is 84644557. The next prime is 84644579. The reversal of 84644561 is 16544648.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 13140625 + 71503936 = 3625^2 + 8456^2 .

It is a cyclic number.

It is not a de Polignac number, because 84644561 - 2² = 84644557 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (84646561) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4610 + ... + 13803.

It is an arithmetic number, because the mean of its divisors is an integer number (21166893).

Almost surely, 2^84644561 is an apocalyptic number.

It is an amenable number.

84644561 is a deficient number, since it is larger than the sum of its proper divisors (23011).

84644561 is a wasteful number, since it uses less digits than its factorization.

84644561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 23010.

The product of its digits is 92160, while the sum is 38.

The square root of 84644561 is about 9200.2478770955. The cubic root of 84644561 is about 439.0692463623.

The spelling of 84644561 in words is "eighty-four million, six hundred forty-four thousand, five hundred sixty-one".