13123720 has 16 divisors (see below), whose sum is σ = 29528460. Its totient is φ = 5249472.

The previous prime is 13123697. The next prime is 13123727. The reversal of 13123720 is 2732131.

It can be written as a sum of positive squares in 2 ways, for example, as 12630916 + 492804 = 3554^2 + 702^2 .

It is not an unprimeable number, because it can be changed into a prime (13123727) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 164007 + ... + 164086.

Almost surely, 2^13123720 is an apocalyptic number.

13123720 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

13123720 is an abundant number, since it is smaller than the sum of its proper divisors (16404740).

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

13123720 is a wasteful number, since it uses less digits than its factorization.

13123720 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 328104 (or 328100 counting only the distinct ones).

The product of its (nonzero) digits is 252, while the sum is 19.

The square root of 13123720 is about 3622.6675254569. The cubic root of 13123720 is about 235.8770306417.

Adding to 13123720 its reverse (2732131), we get a palindrome (15855851).

The spelling of 13123720 in words is "thirteen million, one hundred twenty-three thousand, seven hundred twenty".