20428380 has 144 divisors (see below), whose sum is σ = 73242624. Its totient is φ = 4510080.

The previous prime is 20428379. The next prime is 20428381. The reversal of 20428380 is 8382402.

It is an interprime number because it is at equal distance from previous prime (20428379) and next prime (20428381).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20428381) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 38799 + ... + 39321.

Almost surely, 2^20428380 is an apocalyptic number.

20428380 is a gapful number since it is divisible by the number (20) 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 20428380, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (36621312).

20428380 is an abundant number, since it is smaller than the sum of its proper divisors (52814244).

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

20428380 is a wasteful number, since it uses less digits than its factorization.

20428380 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 576 (or 571 counting only the distinct ones).

The product of its (nonzero) digits is 3072, while the sum is 27.

The square root of 20428380 is about 4519.7765431490. The cubic root of 20428380 is about 273.3660909910.

The spelling of 20428380 in words is "twenty million, four hundred twenty-eight thousand, three hundred eighty".