20364991920 has 1440 divisors, whose sum is σ = 95005794240. Its totient is φ = 3971358720.

The previous prime is 20364991861. The next prime is 20364991921. The reversal of 20364991920 is 2919946302.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20364991921) 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 287 ways as a sum of consecutive naturals, for example, 496707100 + ... + 496707140.

It is an arithmetic number, because the mean of its divisors is an integer number (65976246).

Almost surely, 2^20364991920 is an apocalyptic number.

20364991920 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 20364991920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (47502897120).

20364991920 is an abundant number, since it is smaller than the sum of its proper divisors (74640802320).

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

20364991920 is a wasteful number, since it uses less digits than its factorization.

20364991920 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 128 (or 90 counting only the distinct ones).

The product of its (nonzero) digits is 209952, while the sum is 45.

The spelling of 20364991920 in words is "twenty billion, three hundred sixty-four million, nine hundred ninety-one thousand, nine hundred twenty".