84427205165991 has 24 divisors (see below), whose sum is σ = 125897288100480. Its totient is φ = 54463541126400.

The previous prime is 84427205165987. The next prime is 84427205165993. The reversal of 84427205165991 is 19956150272448.

84427205165991 is a `hidden beast` number, since 8 + 4 + 4 + 2 + 7 + 20 + 5 + 16 + 599 + 1 = 666.

It is not a de Polignac number, because 84427205165991 - 2² = 84427205165987 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (84427205165993) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 12912750 + ... + 18319211.

It is an arithmetic number, because the mean of its divisors is an integer number (5245720337520).

Almost surely, 2^{84427205165991} is an apocalyptic number.

84427205165991 is a deficient number, since it is larger than the sum of its proper divisors (41470082934489).

84427205165991 is a wasteful number, since it uses less digits than its factorization.

84427205165991 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 31241687 (or 31241684 counting only the distinct ones).

The product of its (nonzero) digits is 43545600, while the sum is 63.

The spelling of 84427205165991 in words is "eighty-four trillion, four hundred twenty-seven billion, two hundred five million, one hundred sixty-five thousand, nine hundred ninety-one".