20420028 has 36 divisors (see below), whose sum is σ = 51787008. Its totient is φ = 6784320.

The previous prime is 20420027. The next prime is 20420033. The reversal of 20420028 is 82002402.

It is a tau number, because it is divible by the number of its divisors (36).

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20420027) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 13048 + ... + 14528.

It is an arithmetic number, because the mean of its divisors is an integer number (1438528).

Almost surely, 2^20420028 is an apocalyptic number.

It is an amenable number.

20420028 is an abundant number, since it is smaller than the sum of its proper divisors (31366980).

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

20420028 is a wasteful number, since it uses less digits than its factorization.

20420028 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1874 (or 1869 counting only the distinct ones).

The product of its (nonzero) digits is 256, while the sum is 18.

The square root of 20420028 is about 4518.8525092107. The cubic root of 20420028 is about 273.3288313093.

The spelling of 20420028 in words is "twenty million, four hundred twenty thousand, twenty-eight".