12123920 has 20 divisors (see below), whose sum is σ = 28188300. Its totient is φ = 4849536.

The previous prime is 12123899. The next prime is 12123949. The reversal of 12123920 is 2932121.

It can be written as a sum of positive squares in 2 ways, for example, as 7595536 + 4528384 = 2756^2 + 2128^2 .

It is a tau number, because it is divible by the number of its divisors (20).

It is a Harshad number since it is a multiple of its sum of digits (20).

It is a junction number, because it is equal to n+sod(n) for n = 12123892 and 12123901.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 75695 + ... + 75854.

It is an arithmetic number, because the mean of its divisors is an integer number (1409415).

Almost surely, 2^12123920 is an apocalyptic number.

12123920 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

12123920 is an abundant number, since it is smaller than the sum of its proper divisors (16064380).

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

12123920 is a wasteful number, since it uses less digits than its factorization.

12123920 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 151562 (or 151556 counting only the distinct ones).

The product of its (nonzero) digits is 216, while the sum is 20.

The square root of 12123920 is about 3481.9419868803. The cubic root of 12123920 is about 229.7282234086.

The spelling of 12123920 in words is "twelve million, one hundred twenty-three thousand, nine hundred twenty".