13521157 has 4 divisors (see below), whose sum is σ = 14561260. Its totient is φ = 12481056.

The previous prime is 13521149. The next prime is 13521197. The reversal of 13521157 is 75112531.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 75112531 = 13 ⋅5777887.

It can be written as a sum of positive squares in 2 ways, for example, as 7365796 + 6155361 = 2714^2 + 2481^2 .

It is a cyclic number.

It is not a de Polignac number, because 13521157 - 2³ = 13521149 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 (13521107) 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, 520032 + ... + 520057.

It is an arithmetic number, because the mean of its divisors is an integer number (3640315).

Almost surely, 2^13521157 is an apocalyptic number.

It is an amenable number.

13521157 is a deficient number, since it is larger than the sum of its proper divisors (1040103).

13521157 is a wasteful number, since it uses less digits than its factorization.

13521157 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1040102.

The product of its digits is 1050, while the sum is 25.

The square root of 13521157 is about 3677.1125900630. The cubic root of 13521157 is about 238.2344804429.

Adding to 13521157 its reverse (75112531), we get a palindrome (88633688).

The spelling of 13521157 in words is "thirteen million, five hundred twenty-one thousand, one hundred fifty-seven".