28398805632 has 128 divisors (see below), whose sum is σ = 84558816000. Its totient is φ = 9382367232.

The previous prime is 28398805627. The next prime is 28398805679. The reversal of 28398805632 is 23650889382.

It is a tau number, because it is divible by the number of its divisors (128).

It is a super-2 number, since 2×28398805632² (a number of 22 digits) contains 22 as substring.

It is a Smith number, since the sum of its digits (54) coincides with the sum of the digits of its prime factors.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 354169 + ... + 426887.

It is an arithmetic number, because the mean of its divisors is an integer number (660615750).

Almost surely, 2^28398805632 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 28398805632, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (42279408000).

28398805632 is an abundant number, since it is smaller than the sum of its proper divisors (56160010368).

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

28398805632 is a wasteful number, since it uses less digits than its factorization.

28398805632 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 72855 (or 72837 counting only the distinct ones).

The product of its (nonzero) digits is 4976640, while the sum is 54.

The spelling of 28398805632 in words is "twenty-eight billion, three hundred ninety-eight million, eight hundred five thousand, six hundred thirty-two".