1103621553 has 18 divisors (see below), whose sum is σ = 1600354262. Its totient is φ = 732879360.

The previous prime is 1103621549. The next prime is 1103621591. The reversal of 1103621553 is 3551263011.

1103621553 is a `hidden beast` number, since 1 + 103 + 6 + 2 + 1 + 553 = 666.

It can be written as a sum of positive squares in 3 ways, for example, as 311593104 + 792028449 = 17652^2 + 28143^2 .

It is not a de Polignac number, because 1103621553 - 2² = 1103621549 is a prime.

It is a super-2 number, since 2×1103621553² = 2435961064492263618, which contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (1103621503) by changing a digit.

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 17 ways as a sum of consecutive naturals, for example, 1912401 + ... + 1912977.

Almost surely, 2^1103621553 is an apocalyptic number.

It is an amenable number.

1103621553 is a deficient number, since it is larger than the sum of its proper divisors (496732709).

1103621553 is an frugal number, since it uses more digits than its factorization.

1103621553 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1505 (or 1041 counting only the distinct ones).

The product of its (nonzero) digits is 2700, while the sum is 27.

The square root of 1103621553 is about 33220.8000054183. The cubic root of 1103621553 is about 1033.4117402755.

Adding to 1103621553 its reverse (3551263011), we get a palindrome (4654884564).

The spelling of 1103621553 in words is "one billion, one hundred three million, six hundred twenty-one thousand, five hundred fifty-three".