123289920 has 336 divisors, whose sum is σ = 474299280. Its totient is φ = 29196288.

The previous prime is 123289909. The next prime is 123289937. The reversal of 123289920 is 29982321.

It can be written as a sum of positive squares in 8 ways, for example, as 5089536 + 118200384 = 2256^2 + 10872^2 .

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 1385236 + ... + 1385324.

It is an arithmetic number, because the mean of its divisors is an integer number (1411605).

Almost surely, 2^123289920 is an apocalyptic number.

123289920 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 123289920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (237149640).

123289920 is an abundant number, since it is smaller than the sum of its proper divisors (351009360).

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

123289920 is a wasteful number, since it uses less digits than its factorization.

123289920 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 162 (or 149 counting only the distinct ones).

The product of its (nonzero) digits is 15552, while the sum is 36.

The square root of 123289920 is about 11103.5994164055. The cubic root of 123289920 is about 497.7094158057.

The spelling of 123289920 in words is "one hundred twenty-three million, two hundred eighty-nine thousand, nine hundred twenty".