28739220 has 48 divisors (see below), whose sum is σ = 80777088. Its totient is φ = 7634560.

The previous prime is 28739209. The next prime is 28739233. The reversal of 28739220 is 2293782.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 18265 + ... + 19775.

It is an arithmetic number, because the mean of its divisors is an integer number (1682856).

Almost surely, 2^28739220 is an apocalyptic number.

28739220 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

28739220 is an abundant number, since it is smaller than the sum of its proper divisors (52037868).

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

28739220 is a wasteful number, since it uses less digits than its factorization.

28739220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1840 (or 1838 counting only the distinct ones).

The product of its (nonzero) digits is 12096, while the sum is 33.

The square root of 28739220 is about 5360.8973129505. The cubic root of 28739220 is about 306.3079901292.

The spelling of 28739220 in words is "twenty-eight million, seven hundred thirty-nine thousand, two hundred twenty".