20121128 has 16 divisors (see below), whose sum is σ = 39028500. Its totient is φ = 9713536.

The previous prime is 20121121. The next prime is 20121137. The reversal of 20121128 is 82112102.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 20052484 + 68644 = 4478^2 + 262^2 .

It is not an unprimeable number, because it can be changed into a prime (20121121) 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, 43133 + ... + 43596.

Almost surely, 2^20121128 is an apocalyptic number.

It is an amenable number.

20121128 is a deficient number, since it is larger than the sum of its proper divisors (18907372).

20121128 is a wasteful number, since it uses less digits than its factorization.

20121128 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 86764 (or 86760 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 17.

The square root of 20121128 is about 4485.6580342242. The cubic root of 20121128 is about 271.9886457198.

The spelling of 20121128 in words is "twenty million, one hundred twenty-one thousand, one hundred twenty-eight".