12521612521 has 6 divisors (see below), whose sum is σ = 13763425466. Its totient is φ = 11383284000.

The previous prime is 12521612501. The next prime is 12521612549.

12521612521 is nontrivially palindromic in base 10.

12521612521 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in only one way, i.e., 11431886400 + 1089726121 = 106920^2 + 33011^2 .

It is not a de Polignac number, because 12521612521 - 2⁷ = 12521612393 is a prime.

It is an alternating number because its digits alternate between odd and even.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 12521612521.

It is not an unprimeable number, because it can be changed into a prime (12521612501) 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 5 ways as a sum of consecutive naturals, for example, 51742080 + ... + 51742321.

Almost surely, 2^12521612521 is an apocalyptic number.

12521612521 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

12521612521 is a deficient number, since it is larger than the sum of its proper divisors (1241812945).

12521612521 is a wasteful number, since it uses less digits than its factorization.

12521612521 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 103484423 (or 103484412 counting only the distinct ones).

The product of its digits is 2400, while the sum is 28.

The spelling of 12521612521 in words is "twelve billion, five hundred twenty-one million, six hundred twelve thousand, five hundred twenty-one".