28169858640 has 320 divisors, whose sum is σ = 109170155520. Its totient is φ = 5837598720.

The previous prime is 28169858599. The next prime is 28169858657. The reversal of 28169858640 is 4685896182.

It is a happy number.

It is a Smith number, since the sum of its digits (57) coincides with the sum of the digits of its prime factors.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 7556457 + ... + 7560183.

It is an arithmetic number, because the mean of its divisors is an integer number (341156736).

Almost surely, 2^28169858640 is an apocalyptic number.

28169858640 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 28169858640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (54585077760).

28169858640 is an abundant number, since it is smaller than the sum of its proper divisors (81000296880).

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

28169858640 is a wasteful number, since it uses less digits than its factorization.

28169858640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4170 (or 4164 counting only the distinct ones).

The product of its (nonzero) digits is 6635520, while the sum is 57.

The spelling of 28169858640 in words is "twenty-eight billion, one hundred sixty-nine million, eight hundred fifty-eight thousand, six hundred forty".