28557233640 has 256 divisors, whose sum is σ = 103782873600. Its totient is φ = 7029192960.

The previous prime is 28557233609. The next prime is 28557233651. The reversal of 28557233640 is 4633275582.

28557233640 is a `hidden beast` number, since 2 + 8 + 5 + 572 + 3 + 36 + 40 = 666.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 1124685 + ... + 1149795.

It is an arithmetic number, because the mean of its divisors is an integer number (405401850).

Almost surely, 2^28557233640 is an apocalyptic number.

28557233640 is a gapful number since it is divisible by the number (20) 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 28557233640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (51891436800).

28557233640 is an abundant number, since it is smaller than the sum of its proper divisors (75225639960).

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

28557233640 is a wasteful number, since it uses less digits than its factorization.

28557233640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 25156 (or 25134 counting only the distinct ones).

The product of its (nonzero) digits is 1209600, while the sum is 45.

The spelling of 28557233640 in words is "twenty-eight billion, five hundred fifty-seven million, two hundred thirty-three thousand, six hundred forty".