13120212521 has 4 divisors (see below), whose sum is σ = 14129459652. Its totient is φ = 12110965392.

The previous prime is 13120212499. The next prime is 13120212551. The reversal of 13120212521 is 12521202131.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 12521202131 = 83 ⋅150857857.

It can be written as a sum of positive squares in 2 ways, for example, as 3362724121 + 9757488400 = 57989^2 + 98780^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-13120212521 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 13120212493 and 13120212502.

It is not an unprimeable number, because it can be changed into a prime (13120212551) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 504623546 + ... + 504623571.

It is an arithmetic number, because the mean of its divisors is an integer number (3532364913).

Almost surely, 2^13120212521 is an apocalyptic number.

It is an amenable number.

13120212521 is a deficient number, since it is larger than the sum of its proper divisors (1009247131).

13120212521 is a wasteful number, since it uses less digits than its factorization.

13120212521 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1009247130.

The product of its (nonzero) digits is 240, while the sum is 20.

Adding to 13120212521 its reverse (12521202131), we get a palindrome (25641414652).

The spelling of 13120212521 in words is "thirteen billion, one hundred twenty million, two hundred twelve thousand, five hundred twenty-one".