1155821340 has 24 divisors (see below), whose sum is σ = 3236299920. Its totient is φ = 308219008.

The previous prime is 1155821339. The next prime is 1155821377. The reversal of 1155821340 is 431285511.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a junction number, because it is equal to n+sod(n) for n = 1155821298 and 1155821307.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 9631785 + ... + 9631904.

It is an arithmetic number, because the mean of its divisors is an integer number (134845830).

Almost surely, 2^1155821340 is an apocalyptic number.

1155821340 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1155821340 is an abundant number, since it is smaller than the sum of its proper divisors (2080478580).

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

1155821340 is a wasteful number, since it uses less digits than its factorization.

1155821340 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19263701 (or 19263699 counting only the distinct ones).

The product of its (nonzero) digits is 4800, while the sum is 30.

The square root of 1155821340 is about 33997.3725455365. The cubic root of 1155821340 is about 1049.4543922739.

The spelling of 1155821340 in words is "one billion, one hundred fifty-five million, eight hundred twenty-one thousand, three hundred forty".