12521454335261 has 16 divisors (see below), whose sum is σ = 12870519202800. Its totient is φ = 12177045196800.

The previous prime is 12521454335249. The next prime is 12521454335287. The reversal of 12521454335261 is 16253345412521.

It is a happy number.

It can be written as a sum of positive squares in 8 ways, for example, as 543140994361 + 11978313340900 = 736981^2 + 3460970^2 .

It is a cyclic number.

It is not a de Polignac number, because 12521454335261 - 2¹⁰ = 12521454334237 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12521454335561) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 100488245 + ... + 100612773.

It is an arithmetic number, because the mean of its divisors is an integer number (804407450175).

Almost surely, 2^{12521454335261} is an apocalyptic number.

It is an amenable number.

12521454335261 is a deficient number, since it is larger than the sum of its proper divisors (349064867539).

12521454335261 is a wasteful number, since it uses less digits than its factorization.

12521454335261 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 143200.

The product of its digits is 864000, while the sum is 44.

Adding to 12521454335261 its reverse (16253345412521), we get a palindrome (28774799747782).

The spelling of 12521454335261 in words is "twelve trillion, five hundred twenty-one billion, four hundred fifty-four million, three hundred thirty-five thousand, two hundred sixty-one".