28697888 has 18 divisors (see below), whose sum is σ = 56558691. Its totient is φ = 14333792.

The previous prime is 28697863. The next prime is 28697891. The reversal of 28697888 is 88879682.

It is a powerful number, because all its prime factors have an exponent greater than 1 and also an Achilles number because it is not a perfect power.

It can be written as a sum of positive squares in only one way, i.e., 14348944 + 14348944 = 3788^2 + 3788^2 .

It is an ABA number since it can be written as A⋅B^A, here for A=2, B=3788.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 2 ways as a sum of consecutive naturals, for example, 29831 + ... + 30777.

Almost surely, 2^28697888 is an apocalyptic number.

It is an amenable number.

28697888 is a deficient number, since it is larger than the sum of its proper divisors (27860803).

28697888 is an frugal number, since it uses more digits than its factorization.

28697888 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1904 (or 949 counting only the distinct ones).

The product of its digits is 3096576, while the sum is 56.

The square root of 28697888 is about 5357.0409742693. The cubic root of 28697888 is about 306.1610782790.

The spelling of 28697888 in words is "twenty-eight million, six hundred ninety-seven thousand, eight hundred eighty-eight".