20428912 has 40 divisors (see below), whose sum is σ = 45532800. Its totient is φ = 8697792.

The previous prime is 20428909. The next prime is 20428937. The reversal of 20428912 is 21982402.

It is a Harshad number since it is a multiple of its sum of digits (28).

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 7 ways as a sum of consecutive naturals, for example, 19539 + ... + 20557.

It is an arithmetic number, because the mean of its divisors is an integer number (1138320).

Almost surely, 2^20428912 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 20428912, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (22766400).

20428912 is an abundant number, since it is smaller than the sum of its proper divisors (25103888).

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

20428912 is a wasteful number, since it uses less digits than its factorization.

20428912 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1213 (or 1207 counting only the distinct ones).

The product of its (nonzero) digits is 2304, while the sum is 28.

The square root of 20428912 is about 4519.8353952329. The cubic root of 20428912 is about 273.3684639888.

The spelling of 20428912 in words is "twenty million, four hundred twenty-eight thousand, nine hundred twelve".