20018381920 has 48 divisors (see below), whose sum is σ = 47727353520. Its totient is φ = 7933883904.

The previous prime is 20018381863. The next prime is 20018381921. The reversal of 20018381920 is 2918381002.

It is a super-2 number, since 2×20018381920² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20018381921) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 556482 + ... + 591361.

It is an arithmetic number, because the mean of its divisors is an integer number (994319865).

Almost surely, 2^20018381920 is an apocalyptic number.

20018381920 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20018381920 is an abundant number, since it is smaller than the sum of its proper divisors (27708971600).

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

20018381920 is a wasteful number, since it uses less digits than its factorization.

20018381920 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1147967 (or 1147959 counting only the distinct ones).

The product of its (nonzero) digits is 6912, while the sum is 34.

The spelling of 20018381920 in words is "twenty billion, eighteen million, three hundred eighty-one thousand, nine hundred twenty".