28020456 has 24 divisors (see below), whose sum is σ = 75888930. Its totient is φ = 9340128.

The previous prime is 28020449. The next prime is 28020479. The reversal of 28020456 is 65402082.

It can be written as a sum of positive squares in only one way, i.e., 23328900 + 4691556 = 4830^2 + 2166^2 .

It is a tau number, because it is divible by the number of its divisors (24).

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 194515 + ... + 194658.

Almost surely, 2^28020456 is an apocalyptic number.

It is an amenable number.

28020456 is an abundant number, since it is smaller than the sum of its proper divisors (47868474).

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

28020456 is a wasteful number, since it uses less digits than its factorization.

28020456 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 389185 (or 389178 counting only the distinct ones).

The product of its (nonzero) digits is 3840, while the sum is 27.

The square root of 28020456 is about 5293.4351795408. The cubic root of 28020456 is about 303.7328273582.

It can be divided in two parts, 280 and 20456, that added together give a 4-th power (20736 = 12⁴).

The spelling of 28020456 in words is "twenty-eight million, twenty thousand, four hundred fifty-six".