28787830 has 8 divisors (see below), whose sum is σ = 51818112. Its totient is φ = 11515128.

The previous prime is 28787827. The next prime is 28787839. The reversal of 28787830 is 3878782.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a super-2 number, since 2×28787830² = 1657478312217800, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28787839) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1439382 + ... + 1439401.

It is an arithmetic number, because the mean of its divisors is an integer number (6477264).

Almost surely, 2^28787830 is an apocalyptic number.

28787830 is a deficient number, since it is larger than the sum of its proper divisors (23030282).

28787830 is a wasteful number, since it uses less digits than its factorization.

28787830 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2878790.

The product of its (nonzero) digits is 150528, while the sum is 43.

The square root of 28787830 is about 5365.4291533856. The cubic root of 28787830 is about 306.4805910142.

The spelling of 28787830 in words is "twenty-eight million, seven hundred eighty-seven thousand, eight hundred thirty".