28920140 has 12 divisors (see below), whose sum is σ = 60732336. Its totient is φ = 11568048.

The previous prime is 28920113. The next prime is 28920149. The reversal of 28920140 is 4102982.

It is not an unprimeable number, because it can be changed into a prime (28920149) 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, 722984 + ... + 723023.

It is an arithmetic number, because the mean of its divisors is an integer number (5061028).

Almost surely, 2^28920140 is an apocalyptic number.

28920140 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

28920140 is an abundant number, since it is smaller than the sum of its proper divisors (31812196).

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

28920140 is a wasteful number, since it uses less digits than its factorization.

28920140 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1446016 (or 1446014 counting only the distinct ones).

The product of its (nonzero) digits is 1152, while the sum is 26.

The square root of 28920140 is about 5377.7448805238. The cubic root of 28920140 is about 306.9494058030.

The spelling of 28920140 in words is "twenty-eight million, nine hundred twenty thousand, one hundred forty".