9198781920 has 144 divisors (see below), whose sum is σ = 32755780512. Its totient is φ = 2346347520.

The previous prime is 9198781909. The next prime is 9198781979. The reversal of 9198781920 is 291878919.

It is a tau number, because it is divible by the number of its divisors (144).

It is a Smith number, since the sum of its digits (54) coincides with the sum of the digits of its prime factors.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 105751 + ... + 171990.

It is an arithmetic number, because the mean of its divisors is an integer number (227470698).

Almost surely, 2^9198781920 is an apocalyptic number.

9198781920 is a gapful number since it is divisible by the number (90) formed by its first and last digit.

It is an amenable number.

9198781920 is an abundant number, since it is smaller than the sum of its proper divisors (23556998592).

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

9198781920 is a wasteful number, since it uses less digits than its factorization.

9198781920 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 277785 (or 277774 counting only the distinct ones).

The product of its (nonzero) digits is 653184, while the sum is 54.

The square root of 9198781920 is about 95910.2805751292. The cubic root of 9198781920 is about 2095.2866261972.

The spelling of 9198781920 in words is "nine billion, one hundred ninety-eight million, seven hundred eighty-one thousand, nine hundred twenty".