12435220521 has 48 divisors (see below), whose sum is σ = 19031096448. Its totient is φ = 8112182400.

The previous prime is 12435220481. The next prime is 12435220541. The reversal of 12435220521 is 12502253421.

12435220521 is a `hidden beast` number, since 1 + 2 + 435 + 2 + 205 + 21 = 666.

It is not a de Polignac number, because 12435220521 - 2¹⁵ = 12435187753 is a prime.

It is a super-2 number, since 2×12435220521² (a number of 21 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is not an unprimeable number, because it can be changed into a prime (12435220541) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 2361031 + ... + 2366291.

It is an arithmetic number, because the mean of its divisors is an integer number (396481176).

Almost surely, 2^12435220521 is an apocalyptic number.

It is an amenable number.

12435220521 is a deficient number, since it is larger than the sum of its proper divisors (6595875927).

12435220521 is an equidigital number, since it uses as much as digits as its factorization.

12435220521 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5484 (or 5472 counting only the distinct ones).

The product of its (nonzero) digits is 4800, while the sum is 27.

Adding to 12435220521 its reverse (12502253421), we get a palindrome (24937473942).

The spelling of 12435220521 in words is "twelve billion, four hundred thirty-five million, two hundred twenty thousand, five hundred twenty-one".