11521540 has 24 divisors (see below), whose sum is σ = 24259032. Its totient is φ = 4596480.

The previous prime is 11521519. The next prime is 11521547. The reversal of 11521540 is 4512511.

11521540 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 4 ways, for example, as 2304 + 11519236 = 48^2 + 3394^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (11521547) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 14760 + ... + 15520.

It is an arithmetic number, because the mean of its divisors is an integer number (1010793).

Almost surely, 2^11521540 is an apocalyptic number.

11521540 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

11521540 is an abundant number, since it is smaller than the sum of its proper divisors (12737492).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

11521540 is a wasteful number, since it uses less digits than its factorization.

11521540 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1527 (or 1525 counting only the distinct ones).

The product of its (nonzero) digits is 200, while the sum is 19.

The square root of 11521540 is about 3394.3394055398. The cubic root of 11521540 is about 225.8587103406.

The spelling of 11521540 in words is "eleven million, five hundred twenty-one thousand, five hundred forty".