1172543220 has 144 divisors (see below), whose sum is σ = 3773008512. Its totient is φ = 294117120.

The previous prime is 1172543179. The next prime is 1172543231. The reversal of 1172543220 is 223452711.

1172543220 is a `hidden beast` number, since 117 + 2 + 543 + 2 + 2 + 0 = 666.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 250219 + ... + 254861.

It is an arithmetic number, because the mean of its divisors is an integer number (26201448).

Almost surely, 2^1172543220 is an apocalyptic number.

1172543220 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 1172543220, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1886504256).

1172543220 is an abundant number, since it is smaller than the sum of its proper divisors (2600465292).

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

1172543220 is a wasteful number, since it uses less digits than its factorization.

1172543220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4742 (or 4737 counting only the distinct ones).

The product of its (nonzero) digits is 3360, while the sum is 27.

The square root of 1172543220 is about 34242.4184309461. The cubic root of 1172543220 is about 1054.4911841554.

Adding to 1172543220 its reverse (223452711), we get a palindrome (1395995931).

It can be divided in two parts, 11725 and 43220, that added together give a palindrome (54945).

The spelling of 1172543220 in words is "one billion, one hundred seventy-two million, five hundred forty-three thousand, two hundred twenty".