12503421520 has 40 divisors (see below), whose sum is σ = 29075118984. Its totient is φ = 5000566272.

The previous prime is 12503421499. The next prime is 12503421533. The reversal of 12503421520 is 2512430521.

It can be written as a sum of positive squares in 4 ways, for example, as 4370267664 + 8133153856 = 66108^2 + 90184^2 .

It is a tau number, because it is divible by the number of its divisors (40).

It is a super-2 number, since 2×12503421520² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

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 7 ways as a sum of consecutive naturals, for example, 921022 + ... + 934498.

Almost surely, 2^12503421520 is an apocalyptic number.

12503421520 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

12503421520 is an abundant number, since it is smaller than the sum of its proper divisors (16571697464).

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

12503421520 is a wasteful number, since it uses less digits than its factorization.

12503421520 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 25087 (or 25081 counting only the distinct ones).

The product of its (nonzero) digits is 2400, while the sum is 25.

Subtracting from 12503421520 its reverse (2512430521), we obtain a palindrome (9990990999).

The spelling of 12503421520 in words is "twelve billion, five hundred three million, four hundred twenty-one thousand, five hundred twenty".