28934564778 has 72 divisors (see below), whose sum is σ = 73059081732. Its totient is φ = 8252036352.

The previous prime is 28934564749. The next prime is 28934564783. The reversal of 28934564778 is 87746543982.

28934564778 is a `hidden beast` number, since 2 + 89 + 34 + 56 + 477 + 8 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 23584666329 + 5349898449 = 153573^2 + 73143^2 .

It is a super-3 number, since 3×28934564778³ (a number of 32 digits) contains 333 as substring.

It is a Harshad number since it is a multiple of its sum of digits (63).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 461826 + ... + 520722.

Almost surely, 2^28934564778 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 28934564778, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (36529540866).

28934564778 is an abundant number, since it is smaller than the sum of its proper divisors (44124516954).

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

28934564778 is a wasteful number, since it uses less digits than its factorization.

28934564778 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 59476 (or 59466 counting only the distinct ones).

The product of its digits is 81285120, while the sum is 63.

The spelling of 28934564778 in words is "twenty-eight billion, nine hundred thirty-four million, five hundred sixty-four thousand, seven hundred seventy-eight".