11717521 has 2 divisors, whose sum is σ = 11717522. Its totient is φ = 11717520.

The previous prime is 11717507. The next prime is 11717527. The reversal of 11717521 is 12571711.

11717521 is digitally balanced in base 2 and base 3, because in such bases it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 8065600 + 3651921 = 2840^2 + 1911^2 .

It is a cyclic number.

It is not a de Polignac number, because 11717521 - 2⁷ = 11717393 is a prime.

It is not a weakly prime, because it can be changed into another prime (11717527) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5858760 + 5858761.

It is an arithmetic number, because the mean of its divisors is an integer number (5858761).

Almost surely, 2^11717521 is an apocalyptic number.

It is an amenable number.

11717521 is a deficient number, since it is larger than the sum of its proper divisors (1).

11717521 is an equidigital number, since it uses as much as digits as its factorization.

11717521 is an evil number, because the sum of its binary digits is even.

The product of its digits is 490, while the sum is 25.

The square root of 11717521 is about 3423.0864727611. The cubic root of 11717521 is about 227.1321334132.

The spelling of 11717521 in words is "eleven million, seven hundred seventeen thousand, five hundred twenty-one".