28020890 has 8 divisors (see below), whose sum is σ = 50437620. Its totient is φ = 11208352.

The previous prime is 28020857. The next prime is 28020893. The reversal of 28020890 is 9802082.

It can be written as a sum of positive squares in 2 ways, for example, as 28015849 + 5041 = 5293^2 + 71^2 .

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

It is not an unprimeable number, because it can be changed into a prime (28020893) 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, 1401035 + ... + 1401054.

Almost surely, 2^28020890 is an apocalyptic number.

28020890 is a deficient number, since it is larger than the sum of its proper divisors (22416730).

28020890 is a wasteful number, since it uses less digits than its factorization.

28020890 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2802096.

The product of its (nonzero) digits is 2304, while the sum is 29.

The square root of 28020890 is about 5293.4761735555. The cubic root of 28020890 is about 303.7343954907.

The spelling of 28020890 in words is "twenty-eight million, twenty thousand, eight hundred ninety".