84209643997 has 4 divisors (see below), whose sum is σ = 84250663900. Its totient is φ = 84168624096.

The previous prime is 84209643967. The next prime is 84209644009. The reversal of 84209643997 is 79934690248.

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 15840991321 + 68368652676 = 125861^2 + 261474^2 .

It is a cyclic number.

It is not a de Polignac number, because 84209643997 - 2¹¹ = 84209641949 is a prime.

It is a super-4 number, since 4×84209643997⁴ (a number of 45 digits) contains 4444 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (84209643967) 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, 20506872 + ... + 20510977.

It is an arithmetic number, because the mean of its divisors is an integer number (21062665975).

Almost surely, 2^84209643997 is an apocalyptic number.

It is an amenable number.

84209643997 is a deficient number, since it is larger than the sum of its proper divisors (41019903).

84209643997 is a wasteful number, since it uses less digits than its factorization.

84209643997 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 41019902.

The product of its (nonzero) digits is 23514624, while the sum is 61.

The spelling of 84209643997 in words is "eighty-four billion, two hundred nine million, six hundred forty-three thousand, nine hundred ninety-seven".