123156720 has 320 divisors, whose sum is σ = 461399040. Its totient is φ = 30108672.

The previous prime is 123156703. The next prime is 123156731. The reversal of 123156720 is 27651321.

123156720 = 2303² + 2304² + ... + 2325².

It is a happy number.

It is a super-3 number, since 3×123156720³ (a number of 25 digits) contains 333 as substring.

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

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 1838127 + ... + 1838193.

It is an arithmetic number, because the mean of its divisors is an integer number (1441872).

Almost surely, 2^123156720 is an apocalyptic number.

123156720 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 123156720, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (230699520).

123156720 is an abundant number, since it is smaller than the sum of its proper divisors (338242320).

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

123156720 is a wasteful number, since it uses less digits than its factorization.

123156720 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 149 (or 137 counting only the distinct ones).

The product of its (nonzero) digits is 2520, while the sum is 27.

The square root of 123156720 is about 11097.5997404844. The cubic root of 123156720 is about 497.5301127367.

The spelling of 123156720 in words is "one hundred twenty-three million, one hundred fifty-six thousand, seven hundred twenty".