20947128 has 32 divisors (see below), whose sum is σ = 55449360. Its totient is φ = 6571520.

The previous prime is 20947109. The next prime is 20947133. The reversal of 20947128 is 82174902.

It is a happy number.

It is a plaindrome in base 13.

It is a congruent number.

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 7 ways as a sum of consecutive naturals, for example, 25263 + ... + 26078.

Almost surely, 2^20947128 is an apocalyptic number.

It is an amenable number.

20947128 is an abundant number, since it is smaller than the sum of its proper divisors (34502232).

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

20947128 is a wasteful number, since it uses less digits than its factorization.

20947128 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 51367 (or 51363 counting only the distinct ones).

The product of its (nonzero) digits is 8064, while the sum is 33.

The square root of 20947128 is about 4576.8032511787. The cubic root of 20947128 is about 275.6606836221.

The spelling of 20947128 in words is "twenty million, nine hundred forty-seven thousand, one hundred twenty-eight".