28687198820 has 48 divisors (see below), whose sum is σ = 69135040128. Its totient is φ = 9794787840.

The previous prime is 28687198819. The next prime is 28687198823. The reversal of 28687198820 is 2889178682.

It is a super-2 number, since 2×28687198820² (a number of 22 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 28687198820.

It is not an unprimeable number, because it can be changed into a prime (28687198823) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 391382 + ... + 458861.

It is an arithmetic number, because the mean of its divisors is an integer number (1440313336).

Almost surely, 2^28687198820 is an apocalyptic number.

28687198820 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

28687198820 is an abundant number, since it is smaller than the sum of its proper divisors (40447841308).

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

28687198820 is a wasteful number, since it uses less digits than its factorization.

28687198820 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 850500 (or 850498 counting only the distinct ones).

The product of its (nonzero) digits is 6193152, while the sum is 59.

The spelling of 28687198820 in words is "twenty-eight billion, six hundred eighty-seven million, one hundred ninety-eight thousand, eight hundred twenty".