28252442640 has 320 divisors, whose sum is σ = 93144038400. Its totient is φ = 7073052672.

The previous prime is 28252442599. The next prime is 28252442663. The reversal of 28252442640 is 4624425282.

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, 43938159 + ... + 43938801.

It is an arithmetic number, because the mean of its divisors is an integer number (291075120).

Almost surely, 2^28252442640 is an apocalyptic number.

28252442640 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 28252442640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (46572019200).

28252442640 is an abundant number, since it is smaller than the sum of its proper divisors (64891595760).

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

28252442640 is a wasteful number, since it uses less digits than its factorization.

28252442640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 854 (or 848 counting only the distinct ones).

The product of its (nonzero) digits is 245760, while the sum is 39.

The spelling of 28252442640 in words is "twenty-eight billion, two hundred fifty-two million, four hundred forty-two thousand, six hundred forty".