11561440 has 48 divisors (see below), whose sum is σ = 29801520. Its totient is φ = 4203520.

The previous prime is 11561423. The next prime is 11561447. The reversal of 11561440 is 4416511.

It is a Harshad number since it is a multiple of its sum of digits (22).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (11561447) 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, 1525 + ... + 5044.

It is an arithmetic number, because the mean of its divisors is an integer number (620865).

Almost surely, 2^11561440 is an apocalyptic number.

11561440 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

11561440 is an abundant number, since it is smaller than the sum of its proper divisors (18240080).

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

11561440 is a wasteful number, since it uses less digits than its factorization.

11561440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6595 (or 6587 counting only the distinct ones).

The product of its (nonzero) digits is 480, while the sum is 22.

The square root of 11561440 is about 3400.2117581115. The cubic root of 11561440 is about 226.1191321157.

Adding to 11561440 its reverse (4416511), we get a palindrome (15977951).

Subtracting from 11561440 its reverse (4416511), we obtain a square (7144929 = 2673²).

The spelling of 11561440 in words is "eleven million, five hundred sixty-one thousand, four hundred forty".