28750220 has 12 divisors (see below), whose sum is σ = 60375504. Its totient is φ = 11500080.

The previous prime is 28750217. The next prime is 28750259. The reversal of 28750220 is 2205782.

It is a self number, because there is not a number n which added to its sum of digits gives 28750220.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 718736 + ... + 718775.

It is an arithmetic number, because the mean of its divisors is an integer number (5031292).

Almost surely, 2^28750220 is an apocalyptic number.

28750220 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

28750220 is an abundant number, since it is smaller than the sum of its proper divisors (31625284).

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

28750220 is a wasteful number, since it uses less digits than its factorization.

28750220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1437520 (or 1437518 counting only the distinct ones).

The product of its (nonzero) digits is 2240, while the sum is 26.

The square root of 28750220 is about 5361.9231624483. The cubic root of 28750220 is about 306.3470651644.

The spelling of 28750220 in words is "twenty-eight million, seven hundred fifty thousand, two hundred twenty".