20428406320 has 160 divisors (see below), whose sum is σ = 60499699200. Its totient is φ = 6245019648.

The previous prime is 20428406281. The next prime is 20428406347. The reversal of 20428406320 is 2360482402.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 124411 + ... + 237349.

It is an arithmetic number, because the mean of its divisors is an integer number (378123120).

Almost surely, 2^20428406320 is an apocalyptic number.

20428406320 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 20428406320, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (30249849600).

20428406320 is an abundant number, since it is smaller than the sum of its proper divisors (40071292880).

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

20428406320 is a wasteful number, since it uses less digits than its factorization.

20428406320 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 112995 (or 112989 counting only the distinct ones).

The product of its (nonzero) digits is 18432, while the sum is 31.

Adding to 20428406320 its reverse (2360482402), we get a palindrome (22788888722).

The spelling of 20428406320 in words is "twenty billion, four hundred twenty-eight million, four hundred six thousand, three hundred twenty".