21552003 has 12 divisors (see below), whose sum is σ = 33960888. Its totient is φ = 13061760.

The previous prime is 21551993. The next prime is 21552007. The reversal of 21552003 is 30025512.

It is a happy number.

It is not a de Polignac number, because 21552003 - 2¹² = 21547907 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21552007) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 108750 + ... + 108947.

It is an arithmetic number, because the mean of its divisors is an integer number (2830074).

Almost surely, 2^21552003 is an apocalyptic number.

21552003 is a deficient number, since it is larger than the sum of its proper divisors (12408885).

21552003 is a wasteful number, since it uses less digits than its factorization.

21552003 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 217714 (or 217711 counting only the distinct ones).

The product of its (nonzero) digits is 300, while the sum is 18.

The square root of 21552003 is about 4642.4134886931. The cubic root of 21552003 is about 278.2888970937.

Adding to 21552003 its reverse (30025512), we get a palindrome (51577515).

The spelling of 21552003 in words is "twenty-one million, five hundred fifty-two thousand, three".