20726728 has 32 divisors (see below), whose sum is σ = 42586560. Its totient is φ = 9378880.

The previous prime is 20726711. The next prime is 20726737. The reversal of 20726728 is 82762702.

It is a junction number, because it is equal to n+sod(n) for n = 20726693 and 20726702.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 27525 + ... + 28267.

It is an arithmetic number, because the mean of its divisors is an integer number (1330830).

Almost surely, 2^20726728 is an apocalyptic number.

20726728 is the 2434-th centered heptagonal number.

It is an amenable number.

20726728 is an abundant number, since it is smaller than the sum of its proper divisors (21859832).

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

20726728 is a wasteful number, since it uses less digits than its factorization.

20726728 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1077 (or 1073 counting only the distinct ones).

The product of its (nonzero) digits is 18816, while the sum is 34.

The square root of 20726728 is about 4552.6616390854. The cubic root of 20726728 is about 274.6904638424.

The spelling of 20726728 in words is "twenty million, seven hundred twenty-six thousand, seven hundred twenty-eight".