1103128821 has 32 divisors (see below), whose sum is σ = 1678320000. Its totient is φ = 715685760.

The previous prime is 1103128811. The next prime is 1103128823. The reversal of 1103128821 is 1288213011.

It is not a de Polignac number, because 1103128821 - 2²¹ = 1101031669 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1103128823) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 551395 + ... + 553391.

It is an arithmetic number, because the mean of its divisors is an integer number (52447500).

Almost surely, 2^1103128821 is an apocalyptic number.

It is an amenable number.

1103128821 is a deficient number, since it is larger than the sum of its proper divisors (575191179).

1103128821 is a wasteful number, since it uses less digits than its factorization.

1103128821 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2546 (or 2540 counting only the distinct ones).

The product of its (nonzero) digits is 768, while the sum is 27.

The square root of 1103128821 is about 33213.3831610091. The cubic root of 1103128821 is about 1033.2579221994.

The spelling of 1103128821 in words is "one billion, one hundred three million, one hundred twenty-eight thousand, eight hundred twenty-one".