21235555603 has 4 divisors (see below), whose sum is σ = 21241489248. Its totient is φ = 21229621960.

The previous prime is 21235555591. The next prime is 21235555657. The reversal of 21235555603 is 30655553212.

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 21235555603 - 2¹⁷ = 21235424531 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21235555673) 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, 2961451 + ... + 2968612.

It is an arithmetic number, because the mean of its divisors is an integer number (5310372312).

Almost surely, 2^21235555603 is an apocalyptic number.

21235555603 is a deficient number, since it is larger than the sum of its proper divisors (5933645).

21235555603 is an equidigital number, since it uses as much as digits as its factorization.

21235555603 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5933644.

The product of its (nonzero) digits is 135000, while the sum is 37.

The spelling of 21235555603 in words is "twenty-one billion, two hundred thirty-five million, five hundred fifty-five thousand, six hundred three".