123243904 has 64 divisors (see below), whose sum is σ = 282205440. Its totient is φ = 52517376.

The previous prime is 123243893. The next prime is 123243943. The reversal of 123243904 is 409342321.

It is a tau number, because it is divible by the number of its divisors (64).

It is a super-2 number, since 2×123243904² = 30378119746322432, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (28).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 235387 + ... + 235909.

It is an arithmetic number, because the mean of its divisors is an integer number (4409460).

Almost surely, 2^123243904 is an apocalyptic number.

123243904 is a gapful number since it is divisible by the number (14) 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 123243904, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (141102720).

123243904 is an abundant number, since it is smaller than the sum of its proper divisors (158961536).

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

123243904 is an equidigital number, since it uses as much as digits as its factorization.

123243904 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 807 (or 795 counting only the distinct ones).

The product of its (nonzero) digits is 5184, while the sum is 28.

The square root of 123243904 is about 11101.5271021603. The cubic root of 123243904 is about 497.6474873949.

The spelling of 123243904 in words is "one hundred twenty-three million, two hundred forty-three thousand, nine hundred four".