21202421003 has 4 divisors (see below), whose sum is σ = 21202736208. Its totient is φ = 21202105800.

The previous prime is 21202420999. The next prime is 21202421011. The reversal of 21202421003 is 30012420212.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 21202421003 - 2² = 21202420999 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21202427003) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 11648 + ... + 206253.

It is an arithmetic number, because the mean of its divisors is an integer number (5300684052).

Almost surely, 2^21202421003 is an apocalyptic number.

21202421003 is a deficient number, since it is larger than the sum of its proper divisors (315205).

21202421003 is an equidigital number, since it uses as much as digits as its factorization.

21202421003 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 315204.

The product of its (nonzero) digits is 192, while the sum is 17.

Adding to 21202421003 its reverse (30012420212), we get a palindrome (51214841215).

The spelling of 21202421003 in words is "twenty-one billion, two hundred two million, four hundred twenty-one thousand, three".