1155840 has 144 divisors (see below), whose sum is σ = 4316928. Its totient is φ = 258048.

The previous prime is 1155829. The next prime is 1155841. The reversal of 1155840 is 485511.

It is a super-2 number, since 2×1155840² = 2671932211200, which contains 22 as substring.

It is a hoax number, since the sum of its digits (24) coincides with the sum of the digits of its distinct prime factors.

It is a Harshad number since it is a multiple of its sum of digits (24).

It is an Ulam number.

It is a self number, because there is not a number n which added to its sum of digits gives 1155840.

It is not an unprimeable number, because it can be changed into a prime (1155841) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 26859 + ... + 26901.

2^1155840 is an apocalyptic number.

1155840 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 1155840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2158464).

1155840 is an abundant number, since it is smaller than the sum of its proper divisors (3161088).

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

1155840 is an equidigital number, since it uses as much as digits as its factorization.

1155840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 74 (or 60 counting only the distinct ones).

The product of its (nonzero) digits is 800, while the sum is 24.

The square root of 1155840 is about 1075.0999953493. The cubic root of 1155840 is about 104.9460039835.

The spelling of 1155840 in words is "one million, one hundred fifty-five thousand, eight hundred forty".