28820438 has 16 divisors (see below), whose sum is σ = 44141760. Its totient is φ = 14108616.

The previous prime is 28820431. The next prime is 28820443. The reversal of 28820438 is 83402882.

It is a junction number, because it is equal to n+sod(n) for n = 28820398 and 28820407.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28820431) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 54845 + ... + 55367.

It is an arithmetic number, because the mean of its divisors is an integer number (2758860).

Almost surely, 2^28820438 is an apocalyptic number.

28820438 is a deficient number, since it is larger than the sum of its proper divisors (15321322).

28820438 is a wasteful number, since it uses less digits than its factorization.

28820438 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1051.

The product of its (nonzero) digits is 24576, while the sum is 35.

The square root of 28820438 is about 5368.4670065113. The cubic root of 28820438 is about 306.5962642945.

The spelling of 28820438 in words is "twenty-eight million, eight hundred twenty thousand, four hundred thirty-eight".