28171856620 has 24 divisors (see below), whose sum is σ = 59909774400. Its totient is φ = 11126099712.

The previous prime is 28171856611. The next prime is 28171856653. The reversal of 28171856620 is 2665817182.

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 7 ways as a sum of consecutive naturals, for example, 8913565 + ... + 8916724.

It is an arithmetic number, because the mean of its divisors is an integer number (2496240600).

Almost surely, 2^28171856620 is an apocalyptic number.

28171856620 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

28171856620 is an abundant number, since it is smaller than the sum of its proper divisors (31737917780).

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

28171856620 is a wasteful number, since it uses less digits than its factorization.

28171856620 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17830377 (or 17830375 counting only the distinct ones).

The product of its (nonzero) digits is 322560, while the sum is 46.

The spelling of 28171856620 in words is "twenty-eight billion, one hundred seventy-one million, eight hundred fifty-six thousand, six hundred twenty".