28640560 has 40 divisors (see below), whose sum is σ = 71714160. Its totient is φ = 10574592.

The previous prime is 28640551. The next prime is 28640569. The reversal of 28640560 is 6504682.

It is an interprime number because it is at equal distance from previous prime (28640551) and next prime (28640569).

It is a tau number, because it is divible by the number of its divisors (40).

It is a super-2 number, since 2×28640560² = 1640563354227200, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (28640569) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 12730 + ... + 14809.

It is an arithmetic number, because the mean of its divisors is an integer number (1792854).

Almost surely, 2^28640560 is an apocalyptic number.

28640560 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

28640560 is an abundant number, since it is smaller than the sum of its proper divisors (43073600).

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

28640560 is a wasteful number, since it uses less digits than its factorization.

28640560 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 27565 (or 27559 counting only the distinct ones).

The product of its (nonzero) digits is 11520, while the sum is 31.

The square root of 28640560 is about 5351.6875843046. The cubic root of 28640560 is about 305.9570760131.

The spelling of 28640560 in words is "twenty-eight million, six hundred forty thousand, five hundred sixty".