15521131 has 2 divisors, whose sum is σ = 15521132. Its totient is φ = 15521130.

The previous prime is 15521117. The next prime is 15521137. The reversal of 15521131 is 13112551.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 15521131 - 2¹¹ = 15519083 is a prime.

It is a super-2 number, since 2×15521131² = 481811015038322, which contains 22 as substring.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 15521099 and 15521108.

It is not a weakly prime, because it can be changed into another prime (15521137) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 7760565 + 7760566.

It is an arithmetic number, because the mean of its divisors is an integer number (7760566).

Almost surely, 2^15521131 is an apocalyptic number.

15521131 is a deficient number, since it is larger than the sum of its proper divisors (1).

15521131 is an equidigital number, since it uses as much as digits as its factorization.

15521131 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 150, while the sum is 19.

The square root of 15521131 is about 3939.6866626675. The cubic root of 15521131 is about 249.4447999242. Note that the first 3 decimals are identical.

Adding to 15521131 its reverse (13112551), we get a palindrome (28633682).

The spelling of 15521131 in words is "fifteen million, five hundred twenty-one thousand, one hundred thirty-one".