11861515 has 4 divisors (see below), whose sum is σ = 14233824. Its totient is φ = 9489208.

The previous prime is 11861467. The next prime is 11861527. The reversal of 11861515 is 51516811.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 11861515 - 2¹³ = 11853323 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1186147 + ... + 1186156.

It is an arithmetic number, because the mean of its divisors is an integer number (3558456).

Almost surely, 2^11861515 is an apocalyptic number.

11861515 is a deficient number, since it is larger than the sum of its proper divisors (2372309).

11861515 is an equidigital number, since it uses as much as digits as its factorization.

11861515 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2372308.

The product of its digits is 1200, while the sum is 28.

The square root of 11861515 is about 3444.0550227893. The cubic root of 11861515 is about 228.0587401234.

It can be divided in two parts, 1186 and 1515, that added together give a triangular number (2701 = T₇₃).

The spelling of 11861515 in words is "eleven million, eight hundred sixty-one thousand, five hundred fifteen".