11691540 has 120 divisors (see below), whose sum is σ = 41956992. Its totient is φ = 2669760.

The previous prime is 11691539. The next prime is 11691587. The reversal of 11691540 is 4519611.

11691540 is a `hidden beast` number, since 116 + 9 + 1 + 540 = 666.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 10825 + ... + 11855.

Almost surely, 2^11691540 is an apocalyptic number.

11691540 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 11691540, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (20978496).

11691540 is an abundant number, since it is smaller than the sum of its proper divisors (30265452).

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

11691540 is a wasteful number, since it uses less digits than its factorization.

11691540 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1059 (or 1048 counting only the distinct ones).

The product of its (nonzero) digits is 1080, while the sum is 27.

The square root of 11691540 is about 3419.2893998607. The cubic root of 11691540 is about 226.9641375031.

The spelling of 11691540 in words is "eleven million, six hundred ninety-one thousand, five hundred forty".