28938229380 has 36 divisors (see below), whose sum is σ = 87779296332. Its totient is φ = 7716861120.

The previous prime is 28938229363. The next prime is 28938229381. The reversal of 28938229380 is 8392283982.

28938229380 is a `hidden beast` number, since 2 + 8 + 9 + 38 + 229 + 380 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 10945762884 + 17992466496 = 104622^2 + 134136^2 .

It is a tau number, because it is divible by the number of its divisors (36).

It is a super-2 number, since 2×28938229380² (a number of 22 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (28938229381) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 80383791 + ... + 80384150.

It is an arithmetic number, because the mean of its divisors is an integer number (2438313787).

Almost surely, 2^28938229380 is an apocalyptic number.

28938229380 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

28938229380 is an abundant number, since it is smaller than the sum of its proper divisors (58841066952).

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

28938229380 is a wasteful number, since it uses less digits than its factorization.

28938229380 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 160767956 (or 160767951 counting only the distinct ones).

The product of its (nonzero) digits is 2985984, while the sum is 54.

The spelling of 28938229380 in words is "twenty-eight billion, nine hundred thirty-eight million, two hundred twenty-nine thousand, three hundred eighty".