28101888 has 54 divisors (see below), whose sum is σ = 81031314. Its totient is φ = 9366528.

The previous prime is 28101823. The next prime is 28101889. The reversal of 28101888 is 88810182.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 25887744 + 2214144 = 5088^2 + 1488^2 .

It is a super-2 number, since 2×28101888² = 1579432218329088, which contains 22 as substring.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28101889) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 3795 + ... + 8402.

Almost surely, 2^28101888 is an apocalyptic number.

It is an amenable number.

28101888 is an abundant number, since it is smaller than the sum of its proper divisors (52929426).

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

28101888 is a wasteful number, since it uses less digits than its factorization.

28101888 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12219 (or 12202 counting only the distinct ones).

The product of its (nonzero) digits is 8192, while the sum is 36.

The square root of 28101888 is about 5301.1213908003. The cubic root of 28101888 is about 304.0267751117.

The spelling of 28101888 in words is "twenty-eight million, one hundred one thousand, eight hundred eighty-eight".