82777477728 has 192 divisors, whose sum is σ = 240956964864. Its totient is φ = 24671808000.

The previous prime is 82777477697. The next prime is 82777477729.

It is a happy number.

82777477728 is nontrivially palindromic in base 10.

It is a super-2 number, since 2×82777477728² (a number of 23 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (66).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (82777477729) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 39211393 + ... + 39213503.

It is an arithmetic number, because the mean of its divisors is an integer number (1254984192).

Almost surely, 2^82777477728 is an apocalyptic number.

82777477728 is a gapful number since it is divisible by the number (88) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 82777477728, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (120478482432).

82777477728 is an abundant number, since it is smaller than the sum of its proper divisors (158179487136).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

82777477728 is a wasteful number, since it uses less digits than its factorization.

82777477728 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2729 (or 2721 counting only the distinct ones).

The product of its digits is 120472576, while the sum is 66.

The spelling of 82777477728 in words is "eighty-two billion, seven hundred seventy-seven million, four hundred seventy-seven thousand, seven hundred twenty-eight".