20734428 has 96 divisors (see below), whose sum is σ = 58367232. Its totient is φ = 5644800.

The previous prime is 20734411. The next prime is 20734433. The reversal of 20734428 is 82443702.

It is a junction number, because it is equal to n+sod(n) for n = 20734395 and 20734404.

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 31 ways as a sum of consecutive naturals, for example, 73648 + ... + 73928.

It is an arithmetic number, because the mean of its divisors is an integer number (607992).

Almost surely, 2^20734428 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20734428, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (29183616).

20734428 is an abundant number, since it is smaller than the sum of its proper divisors (37632804).

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

20734428 is a wasteful number, since it uses less digits than its factorization.

20734428 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 355 (or 353 counting only the distinct ones).

The product of its (nonzero) digits is 10752, while the sum is 30.

The square root of 20734428 is about 4553.5072197154. The cubic root of 20734428 is about 274.7244755575.

The spelling of 20734428 in words is "twenty million, seven hundred thirty-four thousand, four hundred twenty-eight".