221001003 has 48 divisors (see below), whose sum is σ = 350752896. Its totient is φ = 133539840.

The previous prime is 221000981. The next prime is 221001031. The reversal of 221001003 is 300100122.

It is a happy number.

221001003 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 221001003 - 2⁵ = 221000971 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (9).

It is not an unprimeable number, because it can be changed into a prime (221002003) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 524733 + ... + 525153.

It is an arithmetic number, because the mean of its divisors is an integer number (7307352).

Almost surely, 2^221001003 is an apocalyptic number.

221001003 is a deficient number, since it is larger than the sum of its proper divisors (129751893).

221001003 is a wasteful number, since it uses less digits than its factorization.

221001003 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 564 (or 561 counting only the distinct ones).

The product of its (nonzero) digits is 12, while the sum is 9.

The square root of 221001003 is about 14866.1024818208. The cubic root of 221001003 is about 604.5952742426.

Adding to 221001003 its reverse (300100122), we get a palindrome (521101125).

The spelling of 221001003 in words is "two hundred twenty-one million, one thousand, three".