123017920 has 56 divisors (see below), whose sum is σ = 302410368. Its totient is φ = 47616000.

The previous prime is 123017911. The next prime is 123017927. The reversal of 123017920 is 29710321.

It is a super-2 number, since 2×123017920² = 30266817282252800, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (123017927) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3720 + ... + 16120.

Almost surely, 2^123017920 is an apocalyptic number.

123017920 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 123017920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (151205184).

123017920 is an abundant number, since it is smaller than the sum of its proper divisors (179392448).

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

123017920 is a wasteful number, since it uses less digits than its factorization.

123017920 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12449 (or 12439 counting only the distinct ones).

The product of its (nonzero) digits is 756, while the sum is 25.

The square root of 123017920 is about 11091.3443729784. The cubic root of 123017920 is about 497.3431337968.

The spelling of 123017920 in words is "one hundred twenty-three million, seventeen thousand, nine hundred twenty".