84889766781 has 24 divisors (see below), whose sum is σ = 131959806264. Its totient is φ = 52390978560.

The previous prime is 84889766771. The next prime is 84889766783. The reversal of 84889766781 is 18766798848.

84889766781 is a `hidden beast` number, since 8 + 488 + 9 + 7 + 6 + 67 + 81 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 1810928025 + 83078838756 = 42555^2 + 288234^2 .

It is not a de Polignac number, because 84889766781 - 2⁷ = 84889766653 is a prime.

It is a super-2 number, since 2×84889766781² (a number of 23 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (84889766783) 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, 4538496 + ... + 4557161.

It is an arithmetic number, because the mean of its divisors is an integer number (5498325261).

Almost surely, 2^84889766781 is an apocalyptic number.

It is an amenable number.

84889766781 is a deficient number, since it is larger than the sum of its proper divisors (47070039483).

84889766781 is a wasteful number, since it uses less digits than its factorization.

84889766781 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9095741 (or 9095738 counting only the distinct ones).

The product of its digits is 260112384, while the sum is 72.

The spelling of 84889766781 in words is "eighty-four billion, eight hundred eighty-nine million, seven hundred sixty-six thousand, seven hundred eighty-one".