20428268 has 72 divisors (see below), whose sum is σ = 45061632. Its totient is φ = 7928928.

The previous prime is 20428241. The next prime is 20428273. The reversal of 20428268 is 86282402.

It is a happy number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 434621 + ... + 434667.

It is an arithmetic number, because the mean of its divisors is an integer number (625856).

Almost surely, 2^20428268 is an apocalyptic number.

20428268 is a gapful number since it is divisible by the number (28) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20428268, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (22530816).

20428268 is an abundant number, since it is smaller than the sum of its proper divisors (24633364).

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

20428268 is a wasteful number, since it uses less digits than its factorization.

20428268 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 139 (or 118 counting only the distinct ones).

The product of its (nonzero) digits is 12288, while the sum is 32.

The square root of 20428268 is about 4519.7641531390. The cubic root of 20428268 is about 273.3655914073.

The spelling of 20428268 in words is "twenty million, four hundred twenty-eight thousand, two hundred sixty-eight".