28215860840 has 128 divisors (see below), whose sum is σ = 67867683840. Its totient is φ = 10520702976.

The previous prime is 28215860837. The next prime is 28215860867. The reversal of 28215860840 is 4806851282.

It is a super-2 number, since 2×28215860840² (a number of 22 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 28215860791 and 28215860800.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 46483817 + ... + 46484423.

It is an arithmetic number, because the mean of its divisors is an integer number (530216280).

Almost surely, 2^28215860840 is an apocalyptic number.

28215860840 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 28215860840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (33933841920).

28215860840 is an abundant number, since it is smaller than the sum of its proper divisors (39651823000).

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

28215860840 is a wasteful number, since it uses less digits than its factorization.

28215860840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1179 (or 1175 counting only the distinct ones).

The product of its (nonzero) digits is 245760, while the sum is 44.

The spelling of 28215860840 in words is "twenty-eight billion, two hundred fifteen million, eight hundred sixty thousand, eight hundred forty".