123320520 has 96 divisors (see below), whose sum is σ = 402175800. Its totient is φ = 32772096.

The previous prime is 123320473. The next prime is 123320521. The reversal of 123320520 is 25023321.

123320520 is a `hidden beast` number, since 123 + 3 + 20 + 520 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 106131204 + 17189316 = 10302^2 + 4146^2 .

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a junction number, because it is equal to n+sod(n) for n = 123320493 and 123320502.

It is not an unprimeable number, because it can be changed into a prime (123320521) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 182904 + ... + 183576.

Almost surely, 2^123320520 is an apocalyptic number.

123320520 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 123320520, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (201087900).

123320520 is an abundant number, since it is smaller than the sum of its proper divisors (278855280).

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

123320520 is a wasteful number, since it uses less digits than its factorization.

123320520 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1199 (or 1192 counting only the distinct ones).

The product of its (nonzero) digits is 360, while the sum is 18.

The square root of 123320520 is about 11104.9772624711. The cubic root of 123320520 is about 497.7505888075.

Adding to 123320520 its reverse (25023321), we get a palindrome (148343841).

The spelling of 123320520 in words is "one hundred twenty-three million, three hundred twenty thousand, five hundred twenty".