20728416 has 24 divisors (see below), whose sum is σ = 54412344. Its totient is φ = 6909440.

The previous prime is 20728403. The next prime is 20728427. The reversal of 20728416 is 61482702.

It is a tau number, because it is divible by the number of its divisors (24).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 107865 + ... + 108056.

It is an arithmetic number, because the mean of its divisors is an integer number (2267181).

Almost surely, 2^20728416 is an apocalyptic number.

It is an amenable number.

20728416 is an abundant number, since it is smaller than the sum of its proper divisors (33683928).

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

20728416 is a wasteful number, since it uses less digits than its factorization.

20728416 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 215934 (or 215926 counting only the distinct ones).

The product of its (nonzero) digits is 5376, while the sum is 30.

The square root of 20728416 is about 4552.8470213703. The cubic root of 20728416 is about 274.6979206379.

The spelling of 20728416 in words is "twenty million, seven hundred twenty-eight thousand, four hundred sixteen".