28145664 has 96 divisors (see below), whose sum is σ = 83538000. Its totient is φ = 9363456.

The previous prime is 28145657. The next prime is 28145671. The reversal of 28145664 is 46654182.

It is an interprime number because it is at equal distance from previous prime (28145657) and next prime (28145671).

It is a tau number, because it is divible by the number of its divisors (96).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 55042 + ... + 55550.

Almost surely, 2^28145664 is an apocalyptic number.

28145664 is a gapful number since it is divisible by the number (24) 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 28145664, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (41769000).

28145664 is an abundant number, since it is smaller than the sum of its proper divisors (55392336).

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

28145664 is an equidigital number, since it uses as much as digits as its factorization.

28145664 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 540 (or 514 counting only the distinct ones).

The product of its digits is 46080, while the sum is 36.

The square root of 28145664 is about 5305.2487217849. The cubic root of 28145664 is about 304.1845601366.

The spelling of 28145664 in words is "twenty-eight million, one hundred forty-five thousand, six hundred sixty-four".