28509861600 has 1440 divisors, whose sum is σ = 124138054656. Its totient is φ = 6295449600.

The previous prime is 28509861571. The next prime is 28509861629. The reversal of 28509861600 is 616890582.

28509861600 is a `hidden beast` number, since 2 + 8 + 509 + 86 + 1 + 60 + 0 = 666.

It is an interprime number because it is at equal distance from previous prime (28509861571) and next prime (28509861629).

It is a tau number, because it is divible by the number of its divisors (1440).

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

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 239 ways as a sum of consecutive naturals, for example, 606592777 + ... + 606592823.

Almost surely, 2^28509861600 is an apocalyptic number.

28509861600 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 28509861600, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (62069027328).

28509861600 is an abundant number, since it is smaller than the sum of its proper divisors (95628193056).

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

28509861600 is a wasteful number, since it uses less digits than its factorization.

28509861600 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 150 (or 128 counting only the distinct ones).

The product of its (nonzero) digits is 207360, while the sum is 45.

The spelling of 28509861600 in words is "twenty-eight billion, five hundred nine million, eight hundred sixty-one thousand, six hundred".