12505621428 has 60 divisors (see below), whose sum is σ = 32847283392. Its totient is φ = 4148761680.

The previous prime is 12505621421. The next prime is 12505621439. The reversal of 12505621428 is 82412650521.

12505621428 is a `hidden beast` number, since 1 + 2 + 5 + 0 + 5 + 621 + 4 + 28 = 666.

12505621428 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 12505621392 and 12505621401.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12505621421) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 23100 + ... + 159827.

Almost surely, 2^12505621428 is an apocalyptic number.

12505621428 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

It is an amenable number.

12505621428 is an abundant number, since it is smaller than the sum of its proper divisors (20341661964).

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

12505621428 is a wasteful number, since it uses less digits than its factorization.

12505621428 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 183154 (or 183143 counting only the distinct ones).

The product of its (nonzero) digits is 38400, while the sum is 36.

The spelling of 12505621428 in words is "twelve billion, five hundred five million, six hundred twenty-one thousand, four hundred twenty-eight".