11511 has 6 divisors (see below), whose sum is σ = 16640. Its totient is φ = 7668.

The previous prime is 11503. The next prime is 11519.

11511 is nontrivially palindromic in base 10.

It is an interprime number because it is at equal distance from previous prime (11503) and next prime (11519).

It is not a de Polignac number, because 11511 - 2³ = 11503 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (9), and also a Moran number because the ratio is a prime number: 1279 = 11511 / (1 + 1 + 5 + 1 + 1).

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 11493 and 11502.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (11519) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 631 + ... + 648.

2¹¹⁵¹¹ is an apocalyptic number.

11511 is a deficient number, since it is larger than the sum of its proper divisors (5129).

11511 is a wasteful number, since it uses less digits than its factorization.

11511 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1285 (or 1282 counting only the distinct ones).

The product of its digits is 5, while the sum is 9.

The square root of 11511 is about 107.2893284535. The cubic root of 11511 is about 22.5789816857.

The spelling of 11511 in words is "eleven thousand, five hundred eleven".