20003561253540 has 120 divisors (see below), whose sum is σ = 64915771730040. Its totient is φ = 5150342195712.

The previous prime is 20003561253509. The next prime is 20003561253541. The reversal of 20003561253540 is 4535216530002.

20003561253540 is a `hidden beast` number, since 2 + 0 + 0 + 0 + 3 + 5 + 61 + 2 + 53 + 540 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 2299444697664 + 17704116555876 = 1516392^2 + 4207626^2 .

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 20003561253495 and 20003561253504.

It is not an unprimeable number, because it can be changed into a prime (20003561253541) by changing a digit.

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 39 ways as a sum of consecutive naturals, for example, 212847457 + ... + 212941416.

It is an arithmetic number, because the mean of its divisors is an integer number (540964764417).

Almost surely, 2^{20003561253540} is an apocalyptic number.

20003561253540 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20003561253540 is an abundant number, since it is smaller than the sum of its proper divisors (44912210476500).

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

20003561253540 is a wasteful number, since it uses less digits than its factorization.

20003561253540 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 425788923 (or 425788912 counting only the distinct ones).

The product of its (nonzero) digits is 108000, while the sum is 36.

Adding to 20003561253540 its reverse (4535216530002), we get a palindrome (24538777783542).

The spelling of 20003561253540 in words is "twenty trillion, three billion, five hundred sixty-one million, two hundred fifty-three thousand, five hundred forty".