28639134720 has 528 divisors, whose sum is σ = 119404621440. Its totient is φ = 6200229888.

The previous prime is 28639134709. The next prime is 28639134731. The reversal of 28639134720 is 2743193682.

28639134720 is a `hidden beast` number, since 2 + 8 + 639 + 1 + 3 + 4 + 7 + 2 + 0 = 666.

It is an interprime number because it is at equal distance from previous prime (28639134709) and next prime (28639134731).

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 (11) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 6126304 + ... + 6130976.

Almost surely, 2^28639134720 is an apocalyptic number.

28639134720 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 28639134720, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (59702310720).

28639134720 is an abundant number, since it is smaller than the sum of its proper divisors (90765486720).

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

28639134720 is a wasteful number, since it uses less digits than its factorization.

28639134720 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4730 (or 4709 counting only the distinct ones).

The product of its (nonzero) digits is 435456, while the sum is 45.

The spelling of 28639134720 in words is "twenty-eight billion, six hundred thirty-nine million, one hundred thirty-four thousand, seven hundred twenty".