20605282640 has 160 divisors (see below), whose sum is σ = 51202437120. Its totient is φ = 7689572352.

The previous prime is 20605282639. The next prime is 20605282699. The reversal of 20605282640 is 4628250602.

It is a self number, because there is not a number n which added to its sum of digits gives 20605282640.

It is a congruent number.

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, 33395612 + ... + 33396228.

It is an arithmetic number, because the mean of its divisors is an integer number (320015232).

Almost surely, 2^20605282640 is an apocalyptic number.

20605282640 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 20605282640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (25601218560).

20605282640 is an abundant number, since it is smaller than the sum of its proper divisors (30597154480).

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

20605282640 is a wasteful number, since it uses less digits than its factorization.

20605282640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 949 (or 943 counting only the distinct ones).

The product of its (nonzero) digits is 46080, while the sum is 35.

The spelling of 20605282640 in words is "twenty billion, six hundred five million, two hundred eighty-two thousand, six hundred forty".