84777813891 has 16 divisors (see below), whose sum is σ = 126322761120. Its totient is φ = 56191842720.

The previous prime is 84777813877. The next prime is 84777813937. The reversal of 84777813891 is 19831877748.

84777813891 is a `hidden beast` number, since 8 + 477 + 7 + 81 + 3 + 89 + 1 = 666.

It is not a de Polignac number, because 84777813891 - 2³¹ = 82630330243 is a prime.

It is not an unprimeable number, because it can be changed into a prime (84777813871) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 9070240 + ... + 9079581.

It is an arithmetic number, because the mean of its divisors is an integer number (7895172570).

Almost surely, 2^84777813891 is an apocalyptic number.

84777813891 is a deficient number, since it is larger than the sum of its proper divisors (41544947229).

84777813891 is a wasteful number, since it uses less digits than its factorization.

84777813891 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18150003 (or 18149997 counting only the distinct ones).

The product of its digits is 18966528, while the sum is 63.

The spelling of 84777813891 in words is "eighty-four billion, seven hundred seventy-seven million, eight hundred thirteen thousand, eight hundred ninety-one".