20723128 has 16 divisors (see below), whose sum is σ = 40109760. Its totient is φ = 10027200.

The previous prime is 20723113. The next prime is 20723137. The reversal of 20723128 is 82132702.

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 3 ways as a sum of consecutive naturals, for example, 41533 + ... + 42028.

It is an arithmetic number, because the mean of its divisors is an integer number (2506860).

Almost surely, 2^20723128 is an apocalyptic number.

It is an amenable number.

20723128 is a deficient number, since it is larger than the sum of its proper divisors (19386632).

20723128 is a wasteful number, since it uses less digits than its factorization.

20723128 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 83598 (or 83594 counting only the distinct ones).

The product of its (nonzero) digits is 1344, while the sum is 25.

The square root of 20723128 is about 4552.2662488040. The cubic root of 20723128 is about 274.6745593714.

The spelling of 20723128 in words is "twenty million, seven hundred twenty-three thousand, one hundred twenty-eight".