13121428 has 6 divisors (see below), whose sum is σ = 22962506. Its totient is φ = 6560712.

The previous prime is 13121417. The next prime is 13121429. The reversal of 13121428 is 82412131.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 11710084 + 1411344 = 3422^2 + 1188^2 .

It is a junction number, because it is equal to n+sod(n) for n = 13121399 and 13121408.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (13121429) by changing a digit.

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 as a sum of consecutive naturals, namely, 1640175 + ... + 1640182.

Almost surely, 2^13121428 is an apocalyptic number.

It is an amenable number.

13121428 is a deficient number, since it is larger than the sum of its proper divisors (9841078).

13121428 is a wasteful number, since it uses less digits than its factorization.

13121428 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3280361 (or 3280359 counting only the distinct ones).

The product of its digits is 384, while the sum is 22.

The square root of 13121428 is about 3622.3511701656. The cubic root of 13121428 is about 235.8632982135.

Adding to 13121428 its reverse (82412131), we get a palindrome (95533559).

The spelling of 13121428 in words is "thirteen million, one hundred twenty-one thousand, four hundred twenty-eight".