20178808920 has 576 divisors, whose sum is σ = 74281484160. Its totient is φ = 4731125760.

The previous prime is 20178808877. The next prime is 20178808927. The reversal of 20178808920 is 2980887102.

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 (20178808927) by changing a digit.

It is a polite number, since it can be written in 143 ways as a sum of consecutive naturals, for example, 276422004 + ... + 276422076.

It is an arithmetic number, because the mean of its divisors is an integer number (128960910).

Almost surely, 2^20178808920 is an apocalyptic number.

20178808920 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 20178808920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (37140742080).

20178808920 is an abundant number, since it is smaller than the sum of its proper divisors (54102675240).

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

20178808920 is a wasteful number, since it uses less digits than its factorization.

20178808920 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 216 (or 178 counting only the distinct ones).

The product of its (nonzero) digits is 129024, while the sum is 45.

The spelling of 20178808920 in words is "twenty billion, one hundred seventy-eight million, eight hundred eight thousand, nine hundred twenty".