11555540 has 24 divisors (see below), whose sum is σ = 24347400. Its totient is φ = 4606848.

The previous prime is 11555501. The next prime is 11555549. The reversal of 11555540 is 4555511.

It can be written as a sum of positive squares in 4 ways, for example, as 770884 + 10784656 = 878^2 + 3284^2 .

It is a super-4 number, since 4×11555540⁴ (a number of 29 digits) contains 4444 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (11555549) 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, 6686 + ... + 8234.

It is an arithmetic number, because the mean of its divisors is an integer number (1014475).

Almost surely, 2^11555540 is an apocalyptic number.

11555540 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

11555540 is an abundant number, since it is smaller than the sum of its proper divisors (12791860).

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

11555540 is a wasteful number, since it uses less digits than its factorization.

11555540 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1931 (or 1929 counting only the distinct ones).

The product of its (nonzero) digits is 2500, while the sum is 26.

The square root of 11555540 is about 3399.3440543728. The cubic root of 11555540 is about 226.0806614211.

It can be divided in two parts, 115 and 55540, that added together give a palindrome (55655).

The spelling of 11555540 in words is "eleven million, five hundred fifty-five thousand, five hundred forty".