20355440520 has 32 divisors (see below), whose sum is σ = 61066321920. Its totient is φ = 5428117440.

The previous prime is 20355440507. The next prime is 20355440527. The reversal of 20355440520 is 2504455302.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is not an unprimeable number, because it can be changed into a prime (20355440527) 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 7 ways as a sum of consecutive naturals, for example, 84814216 + ... + 84814455.

It is an arithmetic number, because the mean of its divisors is an integer number (1908322560).

Almost surely, 2^20355440520 is an apocalyptic number.

20355440520 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20355440520 is an abundant number, since it is smaller than the sum of its proper divisors (40710881400).

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

20355440520 is a wasteful number, since it uses less digits than its factorization.

20355440520 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 169628685 (or 169628681 counting only the distinct ones).

The product of its (nonzero) digits is 24000, while the sum is 30.

Adding to 20355440520 its reverse (2504455302), we get a palindrome (22859895822).

The spelling of 20355440520 in words is "twenty billion, three hundred fifty-five million, four hundred forty thousand, five hundred twenty".