28811388 has 12 divisors (see below), whose sum is σ = 67226600. Its totient is φ = 9603792.

The previous prime is 28811359. The next prime is 28811401. The reversal of 28811388 is 88311882.

It is a tau number, because it is divible by the number of its divisors (12).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1200463 + ... + 1200486.

Almost surely, 2^28811388 is an apocalyptic number.

It is an amenable number.

28811388 is an abundant number, since it is smaller than the sum of its proper divisors (38415212).

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

28811388 is a wasteful number, since it uses less digits than its factorization.

28811388 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2400956 (or 2400954 counting only the distinct ones).

The product of its digits is 24576, while the sum is 39.

The square root of 28811388 is about 5367.6240553899. The cubic root of 28811388 is about 306.5641691696.

The spelling of 28811388 in words is "twenty-eight million, eight hundred eleven thousand, three hundred eighty-eight".