20520605340 has 384 divisors, whose sum is σ = 69407923200. Its totient is φ = 5016453120.

The previous prime is 20520605317. The next prime is 20520605377. The reversal of 20520605340 is 4350602502.

20520605340 is a `hidden beast` number, since 2 + 0 + 5 + 20 + 605 + 34 + 0 = 666.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 127 ways as a sum of consecutive naturals, for example, 85147620 + ... + 85147860.

It is an arithmetic number, because the mean of its divisors is an integer number (180749800).

Almost surely, 2^20520605340 is an apocalyptic number.

20520605340 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 20520605340, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (34703961600).

20520605340 is an abundant number, since it is smaller than the sum of its proper divisors (48887317860).

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

20520605340 is a wasteful number, since it uses less digits than its factorization.

20520605340 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 514 (or 506 counting only the distinct ones).

The product of its (nonzero) digits is 7200, while the sum is 27.

The spelling of 20520605340 in words is "twenty billion, five hundred twenty million, six hundred five thousand, three hundred forty".