20405340330 has 128 divisors (see below), whose sum is σ = 52197861888. Its totient is φ = 5094346752.

The previous prime is 20405340299. The next prime is 20405340341. The reversal of 20405340330 is 3304350402.

It is a self number, because there is not a number n which added to its sum of digits gives 20405340330.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 6899212 + ... + 6902168.

It is an arithmetic number, because the mean of its divisors is an integer number (407795796).

Almost surely, 2^20405340330 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20405340330, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (26098930944).

20405340330 is an abundant number, since it is smaller than the sum of its proper divisors (31792521558).

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

20405340330 is a wasteful number, since it uses less digits than its factorization.

20405340330 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3200.

The product of its (nonzero) digits is 4320, while the sum is 24.

Adding to 20405340330 its reverse (3304350402), we get a palindrome (23709690732).

The spelling of 20405340330 in words is "twenty billion, four hundred five million, three hundred forty thousand, three hundred thirty".