28303830 has 80 divisors (see below), whose sum is σ = 77205744. Its totient is φ = 7439040.

The previous prime is 28303801. The next prime is 28303831. The reversal of 28303830 is 3830382.

28303830 = 213² + 214² + ... + 455².

28303830 is a `hidden beast` number, since 283 + 0 + 383 + 0 = 666.

It is a super-2 number, since 2×28303830² = 1602213585337800, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a junction number, because it is equal to n+sod(n) for n = 28303794 and 28303803.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28303831) by changing a digit.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 67020 + ... + 67440.

Almost surely, 2^28303830 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 28303830, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (38602872).

28303830 is an abundant number, since it is smaller than the sum of its proper divisors (48901914).

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

28303830 is a wasteful number, since it uses less digits than its factorization.

28303830 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 523 (or 514 counting only the distinct ones).

The product of its (nonzero) digits is 3456, while the sum is 27.

The square root of 28303830 is about 5320.1343967986. The cubic root of 28303830 is about 304.7532896987.

The spelling of 28303830 in words is "twenty-eight million, three hundred three thousand, eight hundred thirty".