20956728 has 32 divisors (see below), whose sum is σ = 56422800. Its totient is φ = 6448128.

The previous prime is 20956709. The next prime is 20956739. The reversal of 20956728 is 82765902.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (39).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 33273 + ... + 33896.

Almost surely, 2^20956728 is an apocalyptic number.

It is an amenable number.

20956728 is an abundant number, since it is smaller than the sum of its proper divisors (35466072).

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

20956728 is a wasteful number, since it uses less digits than its factorization.

20956728 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 67191 (or 67187 counting only the distinct ones).

The product of its (nonzero) digits is 60480, while the sum is 39.

The square root of 20956728 is about 4577.8518979976. The cubic root of 20956728 is about 275.7027886527.

The spelling of 20956728 in words is "twenty million, nine hundred fifty-six thousand, seven hundred twenty-eight".