11671521 has 4 divisors (see below), whose sum is σ = 15562032. Its totient is φ = 7781012.

The previous prime is 11671507. The next prime is 11671523. The reversal of 11671521 is 12517611.

11671521 is digitally balanced in base 2 and base 4, because in such bases it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 12517611 = 3 ⋅4172537.

It is a cyclic number.

It is not a de Polignac number, because 11671521 - 2¹⁰ = 11670497 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 11671491 and 11671500.

It is not an unprimeable number, because it can be changed into a prime (11671523) 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, 1945251 + ... + 1945256.

It is an arithmetic number, because the mean of its divisors is an integer number (3890508).

Almost surely, 2^11671521 is an apocalyptic number.

It is an amenable number.

11671521 is a deficient number, since it is larger than the sum of its proper divisors (3890511).

11671521 is an equidigital number, since it uses as much as digits as its factorization.

11671521 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3890510.

The product of its digits is 420, while the sum is 24.

The square root of 11671521 is about 3416.3607830556. The cubic root of 11671521 is about 226.8345226758.

The spelling of 11671521 in words is "eleven million, six hundred seventy-one thousand, five hundred twenty-one".