20008336640 has 144 divisors (see below), whose sum is σ = 50262581376. Its totient is φ = 7616716800.

The previous prime is 20008336639. The next prime is 20008336687. The reversal of 20008336640 is 4663380002.

It is a Harshad number since it is a multiple of its sum of digits (32).

It is a junction number, because it is equal to n+sod(n) for n = 20008336597 and 20008336606.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 6210230 + ... + 6213450.

It is an arithmetic number, because the mean of its divisors is an integer number (349045704).

Almost surely, 2^20008336640 is an apocalyptic number.

20008336640 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 20008336640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (25131290688).

20008336640 is an abundant number, since it is smaller than the sum of its proper divisors (30254244736).

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

20008336640 is a wasteful number, since it uses less digits than its factorization.

20008336640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3476 (or 3462 counting only the distinct ones).

The product of its (nonzero) digits is 20736, while the sum is 32.

The spelling of 20008336640 in words is "twenty billion, eight million, three hundred thirty-six thousand, six hundred forty".