1123171920 has 400 divisors, whose sum is σ = 4285142400. Its totient is φ = 270978048.

The previous prime is 1123171913. The next prime is 1123171921. The reversal of 1123171920 is 291713211.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1123171921) by changing a digit.

It is a polite number, since it can be written in 79 ways as a sum of consecutive naturals, for example, 5643981 + ... + 5644179.

It is an arithmetic number, because the mean of its divisors is an integer number (10712856).

Almost surely, 2^1123171920 is an apocalyptic number.

1123171920 is a gapful number since it is divisible by the number (10) 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 1123171920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2142571200).

1123171920 is an abundant number, since it is smaller than the sum of its proper divisors (3161970480).

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

1123171920 is a wasteful number, since it uses less digits than its factorization.

1123171920 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 304 (or 289 counting only the distinct ones).

The product of its (nonzero) digits is 756, while the sum is 27.

The square root of 1123171920 is about 33513.7571752258. The cubic root of 1123171920 is about 1039.4782639458.

The spelling of 1123171920 in words is "one billion, one hundred twenty-three million, one hundred seventy-one thousand, nine hundred twenty".